Answer:
a) 1.46%.
b) 92.33%.
c) 0.32%.
d) 50%
Step-by-step explanation:
When the distribution is normal, we use the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this question, we have that:
[tex]\mu = 30, \sigma = 5.5[/tex]
a) catch a dragonfly in less than 18 seconds;
This is the pvalue of Z when X = 18. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{18 - 30}{5.5}[/tex]
[tex]Z = -2.18[/tex]
[tex]Z = -2.18[/tex] has a pvalue of 0.0146
So the percentage of shrews is 1.46%.
b) catch a dragonfly in between 22 and 45 seconds;
This is the pvalue of Z when X = 45 subtracted by the pvalue of Z when X = 22.
X = 45
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{45 - 30}{5.5}[/tex]
[tex]Z = 2.73[/tex]
[tex]Z = 2.73[/tex] has a pvalue of 0.9968
X = 22
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{22 - 30}{5.5}[/tex]
[tex]Z = -1.45[/tex]
[tex]Z = -1.45[/tex] has a pvalue of 0.0735
0.9968 - 0.0735 = 0.9233
So the answer is 92.33%.
c) take longer than 45 seconds to catch a dragonfly?
From b), when X = 45, Z = 2.73 has a pvalue of 0.9968
1 - 0.9968 = 0.0032
So the answer for this item is 0.32%.
d) take less than 30 seconds to catch its prey;
This is the pvalue of Z when X = 30.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{30 - 30}{5.5}[/tex]
[tex]Z = 0[/tex]
[tex]Z = 0[/tex] has a pvalue of 0.5
So the answer for d) is 50%.
5 of 5
It is worked out that if 5 ladles full of soup are given to
each person,
140 people can be fed.
The customers have complained in the past that the
portions are too small.
The cook decides to give 7 ladles full of soup to each
person.
How many people can now be fed soup?
people
Answer:
Number of people that can be served 7 ladles = 100 people
Step-by-step explanation:
We are told that;
Initial number of ladles proposed per person = 5
Number of persons to be fed based on 5 ladles = 140 persons
Thus, amount of ladles based on that data is;
140 people x 5 ladle/1 person = 700 ladles full of soup
Now, since the cook decides to give 7 ladles full of soup to each person, the number of people that can be fed will now be;
700 ladles ÷ 7 ladles/person = 100 persons
Which sequences are geometric? Check all that apply.
O 1,5, 25, 125, ...
3, 6, 9, 12,...
3, 6, 12, 24, ...
3, 9, 81, 6, 561, ...
10, 20, 40, 60, ...
Answer:
1, 5, 25, 125, ...
3, 6, 12, 24, ...
Step-by-step explanation:
a geometric progression is a sequence of numbers where each term after the first is found by multiplying the previous one by a fixed, non-zero number called the common ratio1, 5, 25, 125, ...
yes, the common ratio is 53, 6, 9, 12,...
no3, 6, 12, 24, ...
yes, the common ratio is 23, 9, 81, 6, 561, ...
no10, 20, 40, 60, ...
no4x+6y=-10 8x+10y=-26 solve the system of the linear equation
Now by using equation 1 in equation 2 we get,
[tex]4x + 5y = - 13 \\ \\ 4( \frac{ - 5 - 3y}{2} ) + 5y = - 13 \\ \\ \frac{ - 20 - 12y}{2} + 5y = - 13 \\ \\ \frac{ - 20 - 12y + 10y}{2} = - 13 \\ \\ - 20 - 2y = - 26 \\ \\ - 2y = - 26 + 20 \\ \\ - 2y = - 6 \\ \\ y = 3[/tex]Now upon using the value of y in equation 1, we get
[tex]x = \frac{ - 5 - 3y}{2} \\ \\ x = \frac{ - 5 - 3 \times 3}{2} \\ \\ x = \frac{ - 5 - 9}{2} \\ \\ x = \frac{ - 14}{2} = - 7[/tex](12 /`15) ÷ (25/ 16) =
Answer:
[tex]\frac{64}{125}[/tex]
Step-by-step explanation:
[tex]\frac{12}{15} \div \frac{25}{16}[/tex]
[tex]\frac{12}{15} \times \frac{16}{25}[/tex]
[tex]\frac{12 \times 16}{15 \times 25}[/tex]
[tex]\frac{192}{375}[/tex]
[tex]\frac{64}{125}=0.512[/tex]
Answer:
[tex]\frac{64}{125}[/tex]
Step-by-step explanation:
=> [tex]\frac{12}{15} / \frac{25}{16}[/tex]
Changing the division sign into multiplication and inverting the term after the sign.
=> [tex]\frac{12}{15} * \frac{16}{25}[/tex]
=> [tex]\frac{12*16}{15*25}[/tex]
=> [tex]\frac{192}{375}[/tex]
=> [tex]\frac{64}{125}[/tex]
This is the required form.
The following are daily outputs from shift A and shift B at a factory.
Shift A: {77, 91, 82, 68, 75, 72, 85, 65, 70, 79, 94, 86}
Shift B: {68, 93, 53, 100, 77, 86, 91, 88, 72, 74, 66, 82}
Q. Compare the means of the shift outputs. The workers in the shift with the highest mean will earn a bonus. Which shift will earn the bonus?
Answer:
shift B
Step-by-step explanation:
shift a is 78.6 repeating
shift b is 79.3 repeating
mean is when you add them all then divide it by the numbers it has
Answer:
shift B
Step-by-step explanation:
To calculate the mean for a set of data, add all the numbers in that set, then divide by the number of data points in the set.
Determine how many lines of sysmmetry each object had. Then determine whether each object has 180 degree rotational symmetry
Answer:
5, yes.
Step-by-step explanation :
HELP ME QUICK!! The best answer I will mark brainlest!
Answer: 1. (4, 8); 2. (3, 4)
Step-by-step explanation: I tried to get this to you fast but I can give you an explaination if you would like one :)
Solve the following absolute value equation:
|2x-5|=7
x= -6 or x = 1
x = 6 or x = 1
x= -6 or x= -1
x = 6 or x= -1
Answer:
x = 6 x = -1
Step-by-step explanation:
When we have absolute value equations, we get two solutions, one positive and one negative
2x - 5 =7 2x -5= -7
Add 5 to each side
2x-5+5 = 7+5 2x -5+5 = -7+5
2x =12 2x = -2
Divide each side by 2
2x/2 =12/2 2x/2 = -2/2
x = 6 x = -1
Noah has a t-shirt collection. Three-eighths of the t-shirts are blue. Of the blue t-shirts,two-ninths of them have a pocket. What fraction represents the numbers of t-shirts that are blue and have a pocket?
Answer:
1/12
Step-by-step explanation:
blue = (3/8)collection
blue&pocket = (2/9)blue = (2/9)(3/8)collection
blue&pocket = (6/72)collection = (1/12)collection
1/12 of Noah's collection is blue and has a pocket.
Can someone please help me with this one??
Answer:
x = 3.6 cm
Step-by-step explanation:
By the theorem of intersecting secants,
"If two secants are drawn from a point outside the circle, product of the lengths of the secant segment and its external segment are equal."
3(3 + y) = 2(2 + 6 + 3)
9 + 3y = 2 × 11
3y = 22 - 9
3y = 13
y = [tex]\frac{13}{3}[/tex] cm = 4.33 cm
Now we will apply theorem of intersecting chords to determine the value of x.
" When two chords intersect each other in a circle, product of their segments are equal"
[tex]x\times 5=6\times 3[/tex]
[tex]x=\frac{18}{5}[/tex]
[tex]x=3.6[/tex] cm
Therefore, x = 3.6 cm and y = 4.33 cm
2 number cubes are rolled
what is the probability that the first lands on an odd number and the second lands on an even number?
Answer:
1/4
Step-by-step explanation:
1/2 times 1/2
1/2 because there is 3 odds and 3 evens
the total is 6
3/6 equals to 1/2
so 1/2 times 1/2 is 1/4
Provide three logically possible directions of causality, indicating for each direction whether it is a reasonable explanation for the correlation based on the variables involved. Explain why?
Answer:
Step-by-step explanation:
A trapezoid is shown. The lengths of the bases are 4 and 8. The height of the altitude is 4. What is the area of the trapezoid?
Answer:
24
Step-by-step explanation:
Formula
The area of a Trapezoid is given as
A = (b1 + b2)*h/2
Givens
b1 = 8
b2 = 4
h = 4
Solution
Area = (8 + 4)*4/2
Area = 12*4/2
Area = 24
1/2x+4=2/3x+1, solve for x
Answer:
x=18
Step-by-step explanation:
Step 1: Subtract 2/3x from both sides.
1/2x+4=2/3x+1
-2/3x -2/3x
= -1/6x+4=1
Step 2: Subtract 4 from both sides.
-1/6x+4=1
-4 -4
= -1/6x=-3
Step 3: Multiply both sides by 6/(-1).
-1/6x=-3
*6/(-1) * 6/(-1)
x=18
Jana ran 7 days last week. She ran the same number of miles every day, and she ran 28 miles in all. What is Janas rate?
Answer:
Janas rate is of 4 miles per day.
Step-by-step explanation:
Her rate is the number of miles she ran per day.
We can solve this using a rule of three.
In 7 days, she ran 28 miles. How many miles she ran a day, that is, in one day?
1 day - x miles
7 days - 28 miles
[tex]7x = 28[/tex]
[tex]x = \frac{28}{7}[/tex]
[tex]x = 4[/tex]
Janas rate is of 4 miles per day.
ASAP! GIVING BRAINLIEST! Please read the question THEN answer CORRECTLY! NO guessing. I say no guessing because people usually guess on my questions.
Answer:
B. F(x) = 3(x - 2)² - 2
Step-by-step explanation:
→The function F(x) narrowed, meaning the absolute value being multiplied to the function is greater than 1.
→The function F(x) flipped over the x-axis, this means that the number being multiplied has to be a negative.
→The function F(x) shifted to the left 2 units, this means there needs to be a 2 being added.
→The function F(x) shifted downwards 2 units, meaning there needs to be a 2 being subtracted from the whole function.
This gives us the correct answer of "B. F(x) = 3(x - 2)² - 2."
Help me please and thanks
Hey there! :)
Answer:
B.
Step-by-step explanation:
To find the solution to the inequality, we can begin by solving for 'x':
2x + 1 ≥ 3
Subtract 1 from both sides:
2x ≥ 2
Divide both sides by 2:
x ≥ 1.
This means that the graph must contain all values of x greater or equal to one. The only number line that shows solutions greater than 1 is B.
Which values for h and k are used to write the function f(x) = x2 + 12x + 6 in vertex form?
h=6, k=36
h=-6, k=-36
h=6, k=30
h=-6, k=-30
Answer: The answer is h=-6, k=-30
Step-by-step explanation:
d on edg
Determine the value(s) of h such that the matrix is the augmented matrix of a consistent linear system. [Start 2 By 3 Matrix 1st Row 1st Column 1 2nd Column 4 3rd Column negative 2 2nd Row 1st Column 3 2nd Column h 3rd Column negative 6 EndMatrix ]
Answer:
Step-by-step explanation:
Consider the augments matrix (the right most column is the extra vector).
[tex]\left[\begin{matrix} 1 & 4 & -2 \\3 & h & -6\end{matrix}\right][/tex]
By multypling the first row by 3 and substracting it from the second row and saving the result in the second row we get the matrix
[tex]\left[\begin{matrix} 1 & 4 & -2 \\0 & h-12 & 0\end{matrix}\right][/tex]
Note that since the value of the third column in the second row is 0, any value of h gives us a consistent system. An inconsistent system is when we get a row of zeros that is equal to a number different from 0.
The sum of two consecutive even integers is at most 400. The pair of integers with the greatest sum is 196 and 198.
Answer:
Step-by-step explanation: If the sum of two equal even numbers is 400, the numbers will be 200+200. Therefore the largest possible consecutive even numbers which have a sum of 400 or less are 198 and 200 which have a sum of 398.
i guss this would be helpful :]
Answer:
Step-by-step explanation:
Professional basketball coaches may coach at one of three levels: Assistant, Associate, or Head. It is possible to transition from any of these levels (states) to another. Each of these three states is transient because once someone leaves coaching at any level they never return (at least according to our model). On average, annual salary for head coaches is $104,485, for associates is $62,993, and for assistants is $41,389. Using our P matrix, we have solved to find the fundamental matrix (we have called it the (I-Q) inverse matrix): Assist Assoc Head Assist 6 4 2 Assoc 2 6 6 Head 1 2 10 For someone who is a head coach - what is their expected income for the remainder of their professional coaching career?
Answer:
For someone who is a head coach - their expected income for the remainder of their professional coaching career will be
Expected income = 1×$41,389 + 2×$62,993 + 10×$104,485
Expected income = $1,212,225
Step-by-step explanation:
Professional basketball coaches may coach at one of three levels:
AssistantAssociateHeadOn average, the annual salary is given by
Assistant = $41,389Associate = $62,993Head = $104,485Using our P matrix, we have solved to find the fundamental matrix (we have called it the (I-Q) inverse matrix):
Assistant Associate Head
Assistant 6 4 2
Associate 2 6 6
Head 1 2 10
For someone who is a head coach - what is their expected income for the remainder of their professional coaching career?
As per the given P matrix, for someone who is a head coach will be:
Assistant = 1 time
Associate = 2 times
Head = 10 times
Therefore, the expected income will be,
Expected income = 1×$41,389 + 2×$62,993 + 10×$104,485
Expected income = $1,212,225
A car rental company charges a daily rate of $35 plus $0.20 per mile for a certain car. Suppose that you rent that car for a day and your bill (before taxes) is $97. How many miles did you drive?
Answer:
360 miles
Step-by-step explanation:
97= 25+0.2m0.2m= 97-250.2m= 72m= 72/0.2m= 360 milesThe manager of the motor pool wants to know if it costs more to maintain cars that are driven more often. Data are gathered on each car in the motor pool regarding number of miles driven (X) in a given year and maintenance costs for that year (Y) in thousands of dollars. The regression equation is computed as: Y-60+0.08X, and the p-value for the slope estimate is 0.7. What conclusion can we draw from this study? a. Cars that are driven more tend to cost more to maintain. b. There's no statistically significant linear relationship between the number of miles driven and the maintenance cost c. The correlation between the response variable and independent variable is significant. d. The slope estimate is significantly different from zero.
Answer:
b. There's no statistically significant linear relationship between the number of miles driven and the maintenance cost
Step-by-step explanation:
The p-value for the slope estimate show us how strong is the certainty that there are a linear relationship between both variables. In this case, the p-value for the slopes shows if there is a significant relationship between the number of miles driven and the maintenance cost.
If we have a high p-value like 0.7 we can said that there is no certainty in the linear relationship. it means that there's no statistically significant linear relationship between the number of miles driven and the maintenance cost.
Can someone please help me
Answer:
6
Step-by-step explanation:
Similar triangles. MNE is ABC but 3/4 the size. Multiply each side by 3/4 to get lengths.
x = 8 *3/4 = 6
(TEKS 2A.) EF has endpoints E (8,3) and F(-4,9). What is the distance of the given segment?
A 8.544
C 11.250
B 10.345
D 13.416
What expression is equivalent to 6•6•6•6•6
Answer:
6^5
Step-by-step explanation:
6 multiplied with itself 5 times is equal to 6^5
The cost of 4kg of Apple and 6kg of orange is Rs620.If the cost of orange is the same as the cost of 5 kg Apple find the cost of per kg of Apple and orange?
Answer:
The apple cost RS 18.24 per kg, while
the orange cost RS 91.18 per kg.
Step-by-step explanation:
Let the cost of 1kg if apple and orange be RS A and RS O respectively.
From the first line:
4A +6O= 620
2A +3O= 310 -----(1) (÷2 throughout)
From the information given in second line:
O= 5A -----(2)
subst. (2) into (1):
2A +3(5A)= 310
2A +15A= 310 (expand)
17A= 310 (simplify)
A= 310 ÷17 (÷17 on both sides)
A= 18.235 (5 s.f.)
A= 18.24 (2 d.p.)
Subst. into (2):
O= 5(18.235)
O= 91.18 (2 d.p.)
We wish to see if the dial indicating the oven temperature for a certain model of oven is properly calibrated. Four ovens of this model are selected at random. The dial on each is set to 300 °F, and, after one hour, the actual temperature of each is measured. The temperatures measured are 305 °F, 310 °F, 300 °F, and 305 °F. Assuming that the actual temperatures for this model when the dial is set for 300° are Normally distributed with mean μ, we test whether the dial is properly calibrated at 5% of significance level.
Actual Temp: 305, 310, 300, 305
Required:
a. Based on the data, calculate the sample standard deviation and standard error of X bar (round them into two decimal places) Standard Deviation: Standard Error:
b. What is a 95% confidence interval for μ? (upper and lower bound)
c. Provide your test statistic and P-value
d. State your conclusion clearly (statistical conclusion and its interpretation).
e. Even if 5% of significance level looks like default of test, we can use different significance levels as well. If we change the significance level into 10% (= 0.1), how does it affect your conclusion?
Answer:
a. Standard deviation: 4.082
Standard error: 2.041
b. The 95% confidence interval for the actual temperature is (298.5, 311.5).
Upper bound: 311.5
Lower bound: 298.5
c. Test statistic t=2.45
P-value = 0.092
d. There is no enough evidence to claim that the dial of the oven is not properly calibrated. The actual temperature does not significantly differ from 300 °F.
e. If we use a significance level of 10% (a less rigorous test, in which the null hypothesis is rejected with with less requirements), the conclusion changes and now there is enough evidence to claim that the dial is not properly calibrated.
This happens because now the P-value (0.092) is smaller than the significance level (0.10), given statististical evidence for the claim.
Step-by-step explanation:
The mean and standard deviation of the sample are:
[tex]M=\dfrac{1}{4}\sum_{i=1}^{4}(305+310+300+305)\\\\\\ M=\dfrac{1220}{4}=305[/tex]
[tex]s=\sqrt{\dfrac{1}{(n-1)}\sum_{i=1}^{4}(x_i-M)^2}\\\\\\s=\sqrt{\dfrac{1}{3}\cdot [(305-(305))^2+(310-(305))^2+(300-(305))^2+(305-(305))^2]}\\\\\\ s=\sqrt{\dfrac{1}{3}\cdot [(0)+(25)+(25)+(0)]}\\\\\\ s=\sqrt{\dfrac{50}{3}}=\sqrt{16.667}\\\\\\s=4.082[/tex]
We have to calculate a 95% confidence interval for the mean.
The population standard deviation is not known, so we have to estimate it from the sample standard deviation and use a t-students distribution to calculate the critical value.
The sample mean is M=305.
The sample size is N=4.
When σ is not known, s divided by the square root of N is used as an estimate of σM (standard error):
[tex]s_M=\dfrac{s}{\sqrt{N}}=\dfrac{4.082}{\sqrt{4}}=\dfrac{4.082}{2}=2.041[/tex]
The degrees of freedom for this sample size are:
[tex]df=n-1=4-1=3[/tex]
The t-value for a 95% confidence interval and 3 degrees of freedom is t=3.18.
The margin of error (MOE) can be calculated as:
[tex]MOE=t\cdot s_M=3.18 \cdot 2.041=6.5[/tex]
Then, the lower and upper bounds of the confidence interval are:
[tex]LL=M-t \cdot s_M = 305-6.5=298.5\\\\UL=M+t \cdot s_M = 305+6.5=311.5[/tex]
The 95% confidence interval for the actual temperature is (298.5, 311.5).
This is a hypothesis test for the population mean.
The claim is that the actual temperature of the oven when the dial is at 300 °F does not significantly differ from 300 °F.
Then, the null and alternative hypothesis are:
[tex]H_0: \mu=300\\\\H_a:\mu\neq 300[/tex]
The significance level is 0.05.
The sample has a size n=4.
The sample mean is M=305.
As the standard deviation of the population is not known, we estimate it with the sample standard deviation, that has a value of s=4.028.
The estimated standard error of the mean is computed using the formula:
[tex]s_M=\dfrac{s}{\sqrt{n}}=\dfrac{4.082}{\sqrt{4}}=2.041[/tex]
Then, we can calculate the t-statistic as:
[tex]t=\dfrac{M-\mu}{s/\sqrt{n}}=\dfrac{305-300}{2.041}=\dfrac{5}{2.041}=2.45[/tex]
The degrees of freedom for this sample size are:
[tex]df=n-1=4-1=3[/tex]
This test is a two-tailed test, with 3 degrees of freedom and t=2.45, so the P-value for this test is calculated as (using a t-table):
[tex]\text{P-value}=2\cdot P(t>2.45)=0.092[/tex]
As the P-value (0.092) is bigger than the significance level (0.05), the effect is not significant.
The null hypothesis failed to be rejected.
There is not enough evidence to support the claim that the actual temperature of the oven when the dial is at 300 °F does not significantly differ from 300 °F.
If the significance level is 10%, the P-value (0.092) is smaller than the significance level (0.1) and the effect is significant.
The null hypothesis is rejected.
There is enough evidence to support the claim that the actual temperature of the oven when the dial is at 300 °C does not significantly differ from 300 °C.
Saved
250 mg
sing value in
50 mg
10 ml
X
Choice
Tricia has a birthday party. During the party, she opened 36 gifts, which was 60% of all her gifts. After the party, she opened the rest of the gifts and found that 25% of them were the same present, so she returned all but one of the duplicate gifts. How many gifts did she return?
Answer:
She returned 5 gifts.
Step-by-step explanation:
36 gifts is 60% = 0.6 of all the gifts that she received. How many presents are 100% = 1?
36 gifts - 0.6
x gifts - 1
0.6x = 36
x = 36/0.6
x = 60
She received 60 gifts.
She opened the rest of the gifts and found that 25% of them were the same present
The rest is 60 - 36 = 24 gifts.
25% is (1/4)*24 = 6 duplicate figts
She returned all but one of the duplicate gifts.
That is, she returned 6 - 1 = 5 gifts.
