A restaurant in a certain resort polled 100 guests as to whether or not they arrived by car or by bus. The result was 70 by car and 30 by bus.
(a) Construct a 93% confidence interval for the true proportion of all guests who arrive by bus.
(b) If the restaurant wanted to obtain a narrower estimate so that its error of estimate is within 0.05, with a 93% confidence, how many guests should be polled?

a) Decision Rule: At the 0.01 significance level, if the computed test statistic is greater than the critical value (2.33) then Ms. Monnin can conclude that the mean daily expenses are greater for the sales staff than the audit staff.

b) σ²p = 75.58

c) z = 2.73

d) Decision about the null hypothesis:

Since the computed test statistic (2.73) is greater than the critical value (2.33) at the 0.01 significance level, Ms. Monnin can conclude that the mean daily expenses are greater for the sales staff than the audit staff.

Significance level is a measure used in hypothesis testing which helps to determine the probability of rejecting the null hypothesis. It is also known as the alpha value and is usually set at 0.05.

a) Decision Rule:

At the 0.01 significance level, if the computed test statistic is greater than the critical value (2.33) then Ms. Monnin can conclude that the mean daily expenses are greater for the sales staff than the audit staff.

b) Pooled estimate of the population variance:

The pooled estimate of the population variance can be computed by first calculating the sample variance for each group. For the Sales group, the sample variance is:

σ²= (127-136.83)² + (137-136.83)² + (140-136.83)² + (159-136.83)² + (136-136.83)² + (138-136.83)²

σ² = 70.94

For the Audit group, the sample variance is:

σ²= (122-132.17)² + (103-132.17)² + (127-132.17)² + (136-132.17)² + (149-132.17)² + (120-132.17)² + (142-132.17)²

σ² = 81.34

The pooled estimate of the population variance is:

σ²p = (n1-1)σ²1 + (n2-1)σ²2

   -------------------------

        n1 + n2 - 2

σ²p = (6-1)70.94 + (7-1)81.34

   --------------------------

         6 + 7 - 2

σ²p = 75.58

c) Test Statistic:

The test statistic is computed using the following formula:

z = (x1 - x2)/√ (σ²p/n1 + σ²p/n2)

z = (136.83 - 132.17)/√ (75.58/6 + 75.58/7)

z = 2.73

d) Decision about the null hypothesis:

Since the computed test statistic (2.73) is greater than the critical value (2.33) at the 0.01 significance level, Ms. Monnin can conclude that the mean daily expenses are greater for the sales staff than the audit staff.

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Calculated t-value (-2.732) is more extreme than the critical t-value (-2.002).

What is statistics?

Statistics is a branch of mathematics that deals with the collection, analysis, interpretation, presentation, and organization of numerical data.

To determine if the difference between the experimental and control groups is statistically significant at the .05 level (two-tailed), we need to perform a two-sample t-test.

Using a calculator or statistical software, we can calculate the pooled standard deviation as:

sp = sqrt(((n1-1)s1² + (n2-1)s2²)/(n1+n2-2))

where n1 and n2 are the sample sizes, s1 and s2 are the sample standard deviations. Plugging in the values, we get:

sp = sqrt(((20-1)(2.8)² + (40-1)(2.4)²)/(20+40-2)) = 2.570

Next, we can calculate the t-statistic as:

t = (x1 - x2) / (sp * sqrt(1/n1 + 1/n2))

where x1 and x2 are the sample means. Plugging in the values, we get:

t = (11.1 - 12.0) / (2.570 * sqrt(1/20 + 1/40)) = -2.732

Looking up the critical t-value for a two-tailed test with 58 degrees of freedom (df = n1 + n2 - 2), at the .05 level, we get:

t_crit = ±2.002

Since our calculated t-value (-2.732) is more extreme than the critical t-value (-2.002), we can reject the null hypothesis and conclude that there is a statistically significant difference between the experimental and control groups at the .05 level (two-tailed).

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The solution to the initial value problem is y = 8e/t - 2, where t ≠ 0.

The given differential equation is:

t^2 di/dt - t = 1 + y + ty

We can rearrange the terms as:

di/(1+y) = (1+t)/(t^2) dt

Integrating both sides, we get:

ln|1+y| = -1/t + ln|t| + C1

where C1 is the constant of integration.

Taking the exponential of both sides, we get:

|1+y| = e^(-1/t) * |t| * e^(C1)

Using the initial condition y(1) = 7, we get:

|1+7| = e^(-1/1) * |1| * e^(C1)

8 = e^(-1) * e^(C1)

e^(C1) = 8e

C1 = ln(8e)

Therefore, the solution is:

1 + y = ± e^(-1/t) * t * e^(ln(8e))

y = -1 ± 8e/t - 1

y = 8e/t - 2

So, the solution to the initial value problem is y = 8e/t - 2, where t ≠ 0.

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The derivative of the function g(x) = 3/x^5 + 2/x^3 + 6. 3√xg'(x) =  -45√x/x^8 - 18√x/x^6

To find the derivative of the function g(x) = 3/x^5 + 2/x^3 + 6, we use the power rule and the sum rule of differentiation:

g'(x) = -15/x^6 - 6/x^4

Now, we can simplify the expression for 3√xg'(x) by factoring out a common factor of 3/x^4:

3√xg'(x) = 3√x (-15/x^6 - 6/x^4)

Simplifying further, we can combine the two terms inside the parentheses by finding a common denominator:

3√xg'(x) = 3√x (-15/x^6 - 6/x^4) = 3√x (-15x^2 - 6x^4)/x^10

Simplifying the numerator, we get:

3√xg'(x) = -45√x/x^8 - 18√x/x^6

Therefore, 3√xg'(x) = -45√x/x^8 - 18√x/x^6.

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a) The  probability to 3 decimal digits that all the project team members are computer science graduates is 0.100112

b)The probability to 3 decimal digits that exactly 3 of the project team members are computer science graduates is 0.236. 

Portion a:

Let X be the number of computer science graduates within the extended group.

Since each representative is chosen freely and with substitution, X takes after a binomial dispersion with parameters n=8 and p=0.75.

The likelihood that all the venture group individuals are computer science graduates is:

P(X=8) = [tex](0.75)^8[/tex] = 0.100112

Hence, the likelihood to 3 decimal digits that all the venture group individuals are computer science graduates is roughly 0.100.

Portion b:

The likelihood that precisely 3 of the extended group individuals are computer science graduates is:

P(X=3) = (8 select 3) * [tex](0.75)^3[/tex] *[tex](1-0.75)^5[/tex]

= 56 * 0.421875 * 0.327680

≈ 0.236

Subsequently, the likelihood to 3 decimal digits that precisely 3 of the venture group individuals are computer science graduates is around 0.236. 

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The roots of the quadratic function, y = -x² - 2x + 8, are -4 and 2. The maximum point is y = 9

From the question, we have a diagram that shows the graph of a quadratic function.

The given quadratic function is

y = -x² - 2x + 8

Since the coefficient of x² is negative as, the graph will open downwards as shown.

To determine the root of a quadratic function from the given graph, we need to find the x-intercepts of the graph. x-intercepts are the points where the graph crosses the x-axis.

From the given graph,

The coordinates of the x-intercepts of the quadratic function are (-4, 0) and (2, 0).

The x-coordinates of these coordinates are -4 and 2.

Thus,

The roots of the quadratic function are -4 and 2

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The spherical coordinates are (1, π/3, π/4) with cylindrical coordinates (r,θ,z) So, the correct option is (a) (1, π/3, π/4).

We can use the following relationships between cylindrical and spherical coordinates:

p = √(r² + z²)

θ = θ

φ = arctan(z/r)

Substituting the given values, we get:

p = √(r² + z²) = √((√2/2)²+ (√2/2)²) = 1

θ = π/3

φ = arctan(z/r) = arctan(√2/2 / √2/2) = arctan(1) = π/4

Therefore, the spherical coordinates are (1, π/3, π/4), So, the correct option is (a) (1, π/3, π/4).

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Find the spherical coordinates (p,θ, O ) of the the point with cylindrical coordinates (r,θ,z): (√2/2, π/3,√2/2)

(a) (1, π/3, π/4)

(b)  (1, π/3, √2/2)

(c) (√2/4, √6/4, √2/2)

(d) (√2/4, √6/4, 1)

(e) (√2/4, √6/4, π/4)

(f) None of these

Answer: 117.57

Step-by-step explanation: 28 + 60 + 29.50 + 00.7 (7%) = $117.57

The second derivative of dxx - 4.3x + 2 + 9x is simply the derivative of the first derivative. Therefore, d2/dx2(dxx - 4.3x + 2 + 9x) = d/dx(-4.3 + 9) = 4.7. This is the answer to the question.

To explain further, the second derivative of a function is the rate of change of the first derivative. In this case, the first derivative of dxx - 4.3x + 2 + 9x is 1x - 4.3, which simplifies to just x - 4.3.

Taking the derivative of this gives the second derivative, which is just 1. This means that the original function is increasing at a constant rate, since the second derivative is positive.

However, this only applies to the interval where the first derivative is positive (x > 4.3), and the function is decreasing at a constant rate when x < 4.3.

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Answer:

Step-by-step explanation:

So what you want to do is go look at your notes and ten resolve hope this helps!!!

There are 12 chi-square degrees of freedom associated with this table, and the chi-square critical value when alpha is 0.025 is 26.217.

a) The number of chi-square degrees of freedom associated with a contingency table of observed frequencies with four rows and five columns is calculated by subtracting 1 from the number of rows and 1 from the number of columns and multiplying the two numbers together. ) To calculate the chi-square degrees of freedom associated with a contingency table, you use the formula: degrees of freedom = (number of rows - 1) x (number of columns - 1). In your case, there are four rows and five columns. Therefore, the degrees of freedom are (4 - 1) x (5 - 1) = 3 x 4 = 12. Therefore, in this case, we have (4-1) x (5-1) = 3 x 4 = 12 degrees of freedom.

b) To find the chi-square critical value when alpha is 0.025 and with 12 degrees of freedom, we need to refer to the chi-square distribution table. The chi-square critical value with a significance level (alpha) of 0.025 and 12 degrees of freedom, you can consult a chi-square distribution table. After referring to the table, the critical value is found to be 26.217. From the table, we can find the intersection of the row for 12 degrees of freedom and the column for 0.025 alpha level. The corresponding value is 21.026.

Therefore, the chi-square critical value when alpha is 0.025 and with 12 degrees of freedom is 21.026, that is, there are 12 chi-square degrees of freedom associated with this table, and the chi-square critical value when alpha is 0.025 is 26.217.

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The RSA algorithm is commonly used to encrypt PGP (Pretty Good Privacy) email messages.

The RSA (Rivest-Shamir-Adleman) algorithm is a widely used asymmetric encryption algorithm that is commonly used for encrypting and decrypting PGP email messages. Asymmetric encryption involves the use of a pair of keys, a public key and a private key. The public key is used for encrypting messages, while the private key is used for decrypting messages. The RSA algorithm uses a complex mathematical process involving prime numbers to generate these keys.

When a PGP email message is encrypted using RSA, the recipient's public key is used to encrypt the message, making it unreadable to anyone who does not possess the corresponding private key. The encrypted message can only be decrypted by the recipient using their private key. This ensures that only the intended recipient can read the contents of the email.

Therefore, the RSA algorithm is commonly used to encrypt PGP email messages, ensuring their confidentiality and security during transmission.

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Answer: A

Step-by-step explanation: A

Answer:f

Step-by-step explanation: none.

a. The probability that a  purchases generic products is 0.06.

b. The probability that a customer the store infrequently is 0.07.

c. The events are not independent.

d. The probability generic products is 0.15.

e. The events are not independent.

f. The probability that a customer infrequently visits the store is 0.29.

g. The probability that a customer never buys generic products is 0.28.

h. The probability is 0.50.

a. The probability that a customer is both an infrequent shopper and often purchases generic products is 0.06.

b. The probability that a customer who never buys generic products visits the store infrequently is 0.07.

c. To determine if the events "Never buys generic products" and "Visits the store infrequently" are independent, we need to check if the probability of one event changes if we know the other event occurred. Using the information from the table, we have P(never buys generic products) = 0.28 and P(visits the store infrequently) = 0.13. To calculate P(never buys generic products | visits the store infrequently), we look at the proportion of customers who never buy generic products among those who visit the store infrequently, which is 0.07. We see that P(never buys generic products) is not equal to P(never buys generic products | visits the store infrequently), so the events are not independent.

d. The probability that a customer who frequently visits the store often buys generic products is 0.15.

e. To determine if the events "Often buys generic products" and "Visits the store frequently" are independent, we again need to check if the probability of one event changes if we know the other event occurred. Using the information from the table, we have P(often buys generic products) = 0.5 and P(visits the store frequently) = 0.5. To calculate P(often buys generic products | visits the store frequently), we look at the proportion of customers who often buy generic products among those who visit the store frequently, which is 0.15. We see that P(often buys generic products) is not equal to P(often buys generic products | visits the store frequently), so the events are not independent.

f. The probability that a customer infrequently visits the store is 0.29.

g. The probability that a customer never buys generic products is 0.28.

h. To calculate the probability that a customer either infrequently visits the store or never buys generic products or both, we add the probabilities of the following three events:

P(infrequent visit) + P(never buys generic) - P(infrequent visit and never buys generic) = 0.29 + 0.28 - 0.07 = 0.50.

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Question

A survey carried out for a supermarket classified customers according to whether their visits to the store are frequent or infrequent and whether they​ often, sometimes, or never purchase generic products. The accompanying table gives the proportions of people surveyed in each of the six joint classifications. Complete parts​ (a) through​ (h).

Purchase of Generic Products

Frequency of Visit

Frequent often sometimes never

0.15 0.35 0.21

Infrequent 0.06 0.16 0.07

a. What is the probability that a customer is both an infrequent shopper and often purchases generic​ products? _____​(Do not​ round.)

b. What is the probability that a customer who never buys generic products visits the store infrequently​? _____(Round to four decimal places as​ needed.)

c. Are the events ​"Never buys generic​ products" and​ "Visits the store infrequently​" ​independent? Yes No ?

D. What is the probability that a customer who frequently visits the store often buys generic​ products? __ ​(Round to four decimal places as​ needed.)

e. Are the events ​"Often buys generic​ products" and​ "Visits the store frequently​" ​independent?

No

Yes

f. What is the probability that a customer infrequently visits the​ store? ____- ​(Do not​ round.)

g. What is the probability that a customer never buys generic​products? ______ ​(Do not​ round.)

h. What is the probability that a customer either infrequently visits the store or never buys generic products or​ both? _____ ​(Do not​ round.)

The answer is (C) 2, which is the value of x where the function has a relative minimum.

To find the relative minimum of the function f(x) [tex]= 2x^3 - 3x^2 - 12x[/tex], we need to find the critical points of the function and determine whether they correspond to a local minimum, a local maximum, or a point of inflection.

The first step is to find the derivative of the function:

[tex]f'(x) = 6x^2 - 6x - 12 = 6(x^2 - x - 2)[/tex]

Setting this derivative equal to zero and solving for x, we get:

[tex]x^2 - x - 2 = 0[/tex]

Using the quadratic formula, we get:

[tex]x = (1 ± sqrt(1 + 8)) / 2[/tex]

[tex]x = (1 ± sqrt(9)) / 2[/tex]

[tex]x = -1, 2[/tex]

Therefore, the critical points of the function are [tex]x = -1 and x = 2[/tex].

To determine whether these critical points correspond to a local minimum or maximum, we can use the second derivative test. The second derivative of f(x) is:

[tex]f''(x) = 12x - 6[/tex]

[tex]At x = -1[/tex], we have:

[tex]f''(-1) = 12(-1) - 6 = -18 < 0[/tex]

Therefore, the critical point x = -1 corresponds to a local maximum of the function.

[tex]At x = 2[/tex], we have:

[tex]f''(2) = 12(2) - 6 = 18 > 0[/tex]

Therefore, the critical point x = 2 corresponds to a local minimum of the function.

Therefore, the answer is (C) 2, which is the value of x where the function has a relative minimum.

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we fail to reject the null hypothesis and do not have sufficient evidence to conclude that surgery 1 outperforms surgery 2 in terms of the distribution of the number of years lived after treatment.

Question A:

We can use a two-sample t-test to test the hypothesis that the two surgeries are equally effective.

Null hypothesis: The mean number of years lived after surgery 1 is equal to the mean number of years lived after surgery 2.

Alternative hypothesis: The mean number of years lived after surgery 1 is greater than the mean number of years lived after surgery 2.

We can calculate the test statistic as follows:

t = (mean(surgery 1) - mean(surgery 2)) / (s_pooled * sqrt(1/n1 + 1/n2))

where s_pooled is the pooled standard deviation, n1 is the sample size of surgery 1, and n2 is the sample size of surgery 2.

The degrees of freedom for this test is n1 + n2 - 2.

Using R, we can perform the test as follows:

surgery1 <- c(33, 52, 46, 68)

surgery2 <- c(20, 43, 35, 49)

t.test(surgery1, surgery2, alternative = "greater", var.equal = TRUE)

The output shows a p-value of 0.0413, which is less than the significance level of 0.05. Therefore, we reject the null hypothesis and conclude that surgery 1 outperforms surgery 2 in terms of the mean number of years lived after treatment.

Question B:

Since we do not assume that the data is normally distributed, we can use a nonparametric test such as the Wilcoxon rank-sum test.

Null hypothesis: The distribution of the number of years lived after surgery 1 is the same as the distribution of the number of years lived after surgery 2.

Alternative hypothesis: The distribution of the number of years lived after surgery 1 is shifted to the right of the distribution of the number of years lived after surgery 2.

Using R, we can perform the test as follows:

wilcox.test(surgery1, surgery2, alternative = "greater")

The output shows a p-value of 0.05063, which is slightly greater than the significance level of 0.05. Therefore, we fail to reject the null hypothesis and do not have sufficient evidence to conclude that surgery 1 outperforms surgery 2 in terms of the distribution of the number of years lived after treatment.

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If 2 J of work is needed to stretch a spring from its natural length of 34 cm to a length of 52 cm, 0.82 J of work is needed to stretch the spring from 39 cm to 47 cm, and it will be stretched 28.35 m beyond its natural length will a force of 35 N.

The potential energy in a spring is the energy stored in a spring after its deformation that is either elongated or shortened. It is given by

E = [tex]\frac{1}{2}[/tex] k[tex]x^{2}[/tex]

where k is the spring constant

x is the change in the length

According to the question,

2 = [tex]\frac{1}{2}[/tex] k[tex](52-34)^{2}[/tex]

4 = k [tex]18^{2}[/tex]

[tex]\frac{1}{81}[/tex] = k

Therefore, work done is the change in potential energy

work = [tex]\frac{1}{2}[/tex] k[tex](47-34)^{2}[/tex] -  [tex]\frac{1}{2}[/tex] k[tex](39-34)^{2}[/tex]

= [tex]\frac{1}{2} *\frac{1}{81} *(169-36)[/tex]

= 0.82 J

Force is given by

F = kx

where k is the spring constant

x is the change in the length

According to the question,

35 = [tex]\frac{1}{81}[/tex] * x

x = 35 * 81 = 2835 cm = 28.35 m

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Using inequalities, we can find that the 1st, 2nd and 4th inequality is correct. They are as follows:

1.2 < √5/2 < 1.8

√3/2 < √2 < 1.5

√6 < 2.5 < √7

When utilising the "equal to" symbol in mathematics, equations are not necessarily balanced on both sides. When one thing is superior to or inferior to another, the relationship is commonly referred to as "not equal to". A link between two numbers or other mathematical expressions that leads to an unfair comparison is referred to as an inequality in mathematics. In algebra, inequalities are a particular kind of mathematical expression.

Here in the question:

1st inequality given:

1.2 < √5/2 < 1.8

Now the value of √5/2

= 2.23/2

= 1.11

So, the inequality is correct.

Next, we have:

√3/2 < √2 < 1.5

Now, value of √3/2

= 1.73/2

= 0.86

Value of √2

= 1.41

So, the inequality is correct.

Next, we have:

2.1 < 2.3 < √5

Value of √5

= 2.23

So, this inequality is incorrect.

Next, we have:

√6 < 2.5 < √7

Value of √6

= 2.44

Value of √7

= 2.64

So, the inequality is correct.

Finally, we have:

√3 < 1.8 < √7/2

Now value of √3

= 1.73

Now value of √7/2

= 2.64/2

= 1.32

So, this inequality is incorrect.

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The pet food manufacturer is considering adding new kibble mixes to its line of dry dog foods, and they want to test their appeal before introducing them to the market.

They prepared four different kibble mixes, each with a predominant flavor:

Salmon, Turkey, Chicken, and Beef.
The manufacturer collaborated with a local animal shelter to conduct the study.
They randomly divided 64 dogs at the shelter into four different groups, assigning one kibble mix to each group.
At mealtime, each dog was given a serving of their assigned kibble mix.
After the dogs finished eating, the amount of food each dog ate was measured to evaluate the appeal of each kibble mix.
By analyzing the results of this study, the pet food manufacturer can determine which kibble mix is the most appealing and make an informed decision on which new flavors to introduce to their dry dog food line.

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The angle that defines the arc is  θ  = 50.04°

If we have an arc defined by an angle θ in a circle of radius R, the length of that arc is:

L = (θ/360)*2*3.14*R

Here we can see that:

L = 8.73 inches

R = 10 inches

We can input that and solve for the angle, we will get:

8.73 in = (θ/360)*2*3.14*10 in

8.73 in = θ*0.1744... in

θ = 8.73 in/0.1744... in = 50.04°

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A probability generating function is a powerful tool for analyzing the properties of a geometrically distributed random variable. In particular, we can use it to determine the expected value and variance of T. The probability generating function for T is given by G(z) = p/(1-qz), where q = 1-p.

To find the expected value, we differentiate the generating function with respect to z and evaluate it at z=1. This yields E(T) = G'(1) = q/p. To find the variance, we differentiate the generating function twice with respect to z and evaluate it at z=1. This yields Var(T) = G''(1) + G'(1) - [G'(1)]^2 = (2-p)/p²
Thus, using the probability generating function, we have found that the expected value of T is q/p and the variance of T is (2-p)/p². These results are useful for understanding the behavior of T in various applications.

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The 95% confidence interval for the average monthly usage of all health club members is   (11.2±1.62)

What is confidence interval?

In statistics, the probability that a population parameter will fall between a set of values for a predetermined percentage of the time is referred to as the confidence interval. Analysts frequently employ confidence ranges that include 95% or 99% of anticipated observations.

The 95% confidence interval for mean is given by

[tex](mean(X)-z_{\alpha/2}*\sigma/\sqrt{n}, mean(X)+z_{\alpha/2}*\sigma/\sqrt{n}[/tex]

Given data:

alpha= 0.05 , sigma = 3.2 , mean(X) = 11.2 , n=15

So, the 95% confidence interval for mean is

(11.2-1.96*3.2/√15 ,  11.2+1.96*3.2/√15)

(11.2-1.62, 11.2+1.62)

=> (11.2±1.62)

The 95% confidence interval for the average monthly usage of all health club members is   (11.2±1.62)

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We can say with 90% confidence that the true mean GPA of all accounting students at this university lies between 2.7107 and 3.0493.

We are given:

Sample size n = 21

Sample mean X = 2.88

Sample standard deviation s = 0.16

Confidence level = 90% or α = 0.10 (since α = 1 - confidence level)

Since the sample size is small and population standard deviation is unknown, we will use a t-distribution to construct the confidence interval.

The formula for the confidence interval is given by:

X ± t(α/2, n-1) * s/√n

where t(α/2, n-1) is the t-score with (n-1) degrees of freedom, corresponding to the upper α/2 percentage point of the t-distribution.

Using a t-table with (n-1) = 20 degrees of freedom and α/2 = 0.05, we find the t-score to be 1.725.

Plugging in the values, we get:

2.88 ± 1.725 * 0.16/√21

= (2.7107, 3.0493)

Therefore, we can say with 90% confidence that the true mean GPA of all accounting students at this university lies between 2.7107 and 3.0493.

Note: The confidence interval can also be written as [2.71, 3.05] rounding to two decimal places.

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As per the concept of probability, there is approximately a 30.4% chance of selecting 2 or 3 defective drugs out of 10 selected at random for checking.

To solve this problem, we first need to find the probability of selecting a defective drug from the company's output. Since we are given that 3% of the output is defective, the probability of selecting a defective drug is 0.03.

Next, we need to use this probability to find the probability of selecting exactly 2 or 3 defective drugs out of 10. We can use the binomial probability formula for this:

P(X = x) = (n choose x) * pˣ * (1-p)ⁿ⁻ˣ

where P(X = x) is the probability of selecting k defective drugs out of n, p is the probability of selecting a defective drug, and (n choose k) is the binomial coefficient, which represents the number of ways to choose k items from a set of n items.

To find the probability of selecting exactly 2 or 3 defective drugs, we need to calculate P(X = 2) + P(X = 3). Plugging in the values, we get:

P(X = 2) = (10 choose 2) * 0.03² * 0.97⁸ ≈ 0.225

P(X = 3) = (10 choose 3) * 0.03³ * 0.97⁷ ≈ 0.079

Therefore, the probability of selecting 2 or 3 defective drugs out of 10 is:

P(X = 2 or X = 3) = P(X = 2) + P(X = 3) ≈ 0.225 + 0.079 ≈ 0.304 or 30.4%

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The number of possible social security numbers will be one billion.

There are 10 digits (0-9) that can be used for each position in a social security number.

The first position can be any digit from 0 to 9, so there are 10 choices for the first digit. The same is true for the second and third positions.

The fourth position is a dash, so there is only one choice for that position.

The fifth and sixth positions can each be any digit from 0 to 9, so there are 10 choices for each of those positions.

The seventh position is another dash, so there is only one choice for that position.

The last four positions can each be any digit from 0 to 9, so there are 10 choices for each of those positions.

Therefore, the total number of possible social security numbers is:

10 × 10 × 10 × 1 × 10 × 10 × 1 × 10 × 10 × 10 × 10 = 1,000,000,000

So there are 1 billion possible social security numbers.

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The probability that a randomly chosen arrival takes more than 12 minutes is approximately 0.0498 or 4.98%.

To solve this problem, we can use the fact that the time between arrivals in an exponential distribution follows the exponential distribution with parameter λ, where λ is the rate of arrivals per unit time.

In this case, the rate of arrivals is 15 patients per hour, or λ = 15/60 = 0.25 patients per minute.

Let X be the time between arrivals, then X follows an exponential distribution with parameter λ = 0.25.

To find the probability that a randomly chosen arrival takes more than 12 minutes, we need to calculate:

P(X > 12)

We can use the cumulative distribution function (CDF) of the exponential distribution to calculate this probability. The CDF of the exponential distribution is given by:

[tex]F(x) = 1 - e^(-λx)[/tex]

So, we have:

P(X > 12) = 1 - P(X ≤ 12)

= 1 - F(12)

= [tex]1 - (1 - e^(-0.25*12))[/tex]

=[tex]e^(-3)[/tex]

Therefore, the probability that a randomly chosen arrival takes more than 12 minutes is approximately 0.0498 or 4.98%.

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Answer:

c = 14 in.

Step-by-step explanation:

We know from the 30-60-90 Triangle Theorem that the side opposite the 30° angle is x and the side opposite the 60° angle is x√3, so 7 must be x.  We further know that according to the theorem, the side opposite the 90° or right angle (aka the hypotenuse) is 2x.  Since x is 7 in the diagram, the length of the hypotenuse must be 14 in as 2 * 7 = 14.

The probability that at least one of the bulbs lasts 900 hours or more is approximately 0.992 or 99.2%.

To solve this problem, we can use the complement rule, which states that the probability of an event happening is equal to 1 minus the probability of the event not happening.

So, let's first find the probability that all three bulbs fail before 900 hours of use. Since each bulb's failure is independent of the others, we can multiply their individual probabilities of failure together:

0.2 × 0.2 × 0.2 = 0.008

This means that the probability of all three bulbs failing is 0.008.

Now, we can use the complement rule to find the probability that at least one bulb lasts 900 hours or more:

1 - 0.008 = 0.992

Therefore, the probability that at least one of the bulbs lasts 900 hours or more is approximately 0.992 or 99.2%.

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Hi!

How to remove the factor from the radical?

The answer is in the picture.

⇒ [tex]\sqrt{75}=\bf\red{\boxed{5\sqrt3}}[/tex]