In the western region of the state the times of all boys running in this event are normally distributed with standard deviation 12 seconds, but with mean 5 minutes 22 seconds. Find the proportion of boys from this region who qualify to run in this event in the state meet. (Hint: normalcdf)

Answer:

The test statistic for the hypothesis test is -1.202.

Step-by-step explanation:

We are given that a report on the nightly news broadcast stated that 10 out of 129 households with pet dogs were burglarized and 23 out of 197 without pet dogs were burglarized.

Let [tex]p_1[/tex] = population proportion of households with pet dogs who were burglarized.

[tex]p_2[/tex] = population proportion of households without pet dogs who were burglarized.

SO, Null Hypothesis, [tex]H_0[/tex] : [tex]p_1=p_2[/tex]     {means that both population proportions are equal}

Alternate Hypothesis, [tex]H_A[/tex] : [tex]p_1\neq p_2[/tex]     {means that both population proportions are not equal}

The test statistics that would be used here Two-sample z-test for proportions;

                           T.S. =  [tex]\frac{(\hat p_1-\hat p_2)-(p_1-p_2)}{\sqrt{\frac{\hat p_1(1-\hat p_1)}{n_1}+\frac{\hat p_2(1-\hat p_2)}{n_2} } }[/tex]  ~ N(0,1)

where, [tex]\hat p_1[/tex] = sample proportion of households with pet dogs who were burglarized = [tex]\frac{10}{129}[/tex] = 0.08

[tex]\hat p_2[/tex] = sample proportion of households without pet dogs who were burglarized = [tex]\frac{23}{197}[/tex] = 0.12

[tex]n_1[/tex] = sample of households with pet dogs = 129

[tex]n_2[/tex] = sample of households without pet dogs = 197

So, the test statistics  =  [tex]\frac{(0.08-0.12)-(0)}{\sqrt{\frac{0.08(1-0.08)}{129}+\frac{0.12(1-0.12)}{197} } }[/tex] 

                                     =  -1.202

The value of z test statistics is -1.202.

Answer:

x = 1.5

Step-by-step explanation:

Given

[tex]\frac{x}{2} \geq 0.75[/tex]

[tex]\frac{x}{2} < 2.5[/tex]

Required

Find the value of x.

First, the inequalities need to be rewritten and merged;

if [tex]\frac{x}{2} \geq 0.75[/tex], then

[tex]0.75 \leq \frac{x}{2}[/tex]

Multiply both sides by 2

[tex]2 * 0.75 \leq \frac{x}{2} * 2[/tex]

[tex]1.5 \leq x[/tex]

Similarly;

[tex]\frac{x}{2} < 2.5[/tex]

Multiply both sides by 2

[tex]2 * \frac{x}{2} < 2.5 * 2[/tex]

[tex]x < 5[/tex]

Merging these results together; to give

[tex]1.5 \leq x < 5[/tex]

This means that the range of values of x is from 1.5 to 4.9999....

From the question, x is the smallest rational number; from the range above ([tex]1.5 \leq x < 5[/tex]), the minimum value of x is 1.5 and 1.5 is a rational number;

Hence, x  = 1.5

Answer:

B

Step-by-step explanation:

Answer:

Step-by-step explanation:

12$

Answer:

Hello! Here is your answer

Step-by-step explanation:

112=4(28)

a=4b

You can only have one variable so:

Combine b to a:

a-b=84

4b-b=84

Divide both sides by 3:

3b/3=84/3

b=28

But that is not it:

Sum of both cards:

a+b

a=112

b=28

112+28=140

          = 140

I hope I was of help.  If not please let me know! Thank you! Good luck!

Answer:  C

Step-by-step explanation:

In order to find the inverse, transpose the matrix then find the determinant of each 2 x 2 matrix within it.

[tex]Q=\left[\begin{array}{ccc}2&2&3\\1&1&1\\3&2&1\end{array}\right] \qquad \rightarrow \qquad Q^T=\left[\begin{array}{ccc}2&1&3\\2&1&2\\3&1&1\end{array}\right][/tex]

[tex]det\left[\begin{array}{cc}1&2\\1&1\end{array}\right] =\bold{-1}\qquad det\left[\begin{array}{cc}2&2\\3&1\end{array}\right]=\bold{-4}\qquad det\left[\begin{array}{cc}2&1\\3&1\end{array}\right] =\bold{-1}\\\\\\\\det\left[\begin{array}{cc}1&3\\1&1\end{array}\right] =\bold{-2}\qquad det\left[\begin{array}{cc}2&3\\3&1\end{array}\right]=\bold{-7}\qquad det\left[\begin{array}{cc}2&1\\3&1\end{array}\right] =\bold{-1}\\[/tex]

[tex]det\left[\begin{array}{cc}1&3\\1&2 \end{array}\right] =\bold{-1}\qquad det\left[\begin{array}{cc}2&3\\2&2\end{array}\right]=\bold{-2}\qquad det\left[\begin{array}{cc}2&1\\2&1\end{array}\right] =\bold{0}[/tex]

[tex]Q^{-1}=\large\left[\begin{array}{ccc}1&-4&1\\-2&7&-1\\-1&-2&0\end{array}\right][/tex]

Answer:

The 95% confidence interval for the mean of all body temperatures is between 97.76 ºF and 99.12 ºF

Step-by-step explanation:

We have the standard deviation for the sample, so we use the t-distribution to solve this question.

The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So

df = 10 - 1 = 9

95% confidence interval

Now, we have to find a value of T, which is found looking at the t table, with 9 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.95}{2} = 0.975[/tex]. So we have T = 2.2622

The margin of error is:

M = T*s = 2.2622*0.3 = 0.68

In which s is the standard deviation of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 98.44 - 0.68 = 97.76 ºF

The upper end of the interval is the sample mean added to M. So it is 98.44 + 0.68 = 99.12 ºF

The 95% confidence interval for the mean of all body temperatures is between 97.76 ºF and 99.12 ºF

Answer:

[tex]x = \frac{-41}{17} , y = \frac{-1}{17}[/tex]

Step-by-step explanation:

Step(i):-

Given equations are  2 x+3 y=-5  ...(i)

                                   5 x-y=-12 ...(ii)

Multiply equation (ii) by '3'

                                    2 x + 3 y  = -5  

                                   15 x - 3 y  = - 36

                                  17 x  = - 41

                                   [tex]x = \frac{-41}{17}[/tex]

Step(ii):-

Substitute [tex]x = \frac{-41}{17}[/tex]  in equation (i)

                             2 ([tex]\frac{-41}{17}[/tex]+3 y=-5

                                 3 y = - 5 + [tex]\frac{82}{17}[/tex]

                               [tex]3 y = \frac{-85 + 82}{17} = \frac{-3}{17}[/tex]

                               [tex]y = \frac{-1}{17}[/tex]

The solution of the two equations

 ( x, y ) = [tex](\frac{-41}{17} , \frac{-1}{17})[/tex]

Answer:

900000cubic feet

Step-by-step explanation:

capacity of dump hole= 250*120*30

= 900000cubic feet

Answer:

The probability that both the male and female student are non-smokers is 0.72.

Step-by-step explanation:

The complete question is:

At a local college,178 of the male students are smokers and 712 are non-smokers. Of the female students,80 are smokers and 720 are nonsmokers. A male student and a female student from the college are randomly selected for a survey. What is the probability that both are non-smokers?

Solution:

Let, X denote the number of non-smoker male students and Y denote the number of non-smoker female students.

It is provided that:

X' = 178

X = 712

Tx = 890

Y' = 80

Y = 720

Ty = 800

Compute the probability of selecting a non-smoker male student as follows:

[tex]P (\text{Non-smoker Male student})=\frac{712}{890}=0.80[/tex]

Compute the probability of selecting a non-smoker female student as follows:

[tex]P (\text{Non-smoker Female student})=\frac{720}{800}=0.90[/tex]

Compute the probability that both the male and female student are non-smokers as follows:[tex]P(\text{Non-smoker Male and Female})=P(\text{Non-smoker Male})\times P(\text{Non-smoker Female})[/tex]The event of any female student being a non-smoker is independent of the male students.

[tex]P(\text{Non-smoker Male and Female})=0.80\times 0.90[/tex]

                                                 [tex]=0.72[/tex]

Thus, the probability that both the male and female student are non-smokers is 0.72.

Answer:

Step-by-step explanation:

it is increasing in [tex]]-\infty;3/2][/tex]

because this is like

[tex]f(x)=ax^2+bx+c[/tex]

where a > 0

and -b/a=3/2

[tex]solution \\ x = 10 \\ now \\ (7x - 5) \\ = (7 \times 10 - 5) \\ = (70 - 5) \\ = 65[/tex]

Hope it helps....

Good luck on your assignment

Answer:

65

Step-by-step explanation:

= 7x-5

Putting x = 10

= 7(10)-5

= 70-5

= 65

Answer:

Looks like it's none.

Step-by-step explanation:

[tex]\frac{1}{7}*\frac{1}{8}=\frac{1}{56}[/tex]

Answer:

Step-by-step explanation:B and D I belive.

Answer:

what is this boiii?

Answer:

250

Step-by-step explanation:

if x=50

5(x)=5*50=250

Hope it helps..Pls mark as Brainliest!!

Answer:

m > 82.28

Step-by-step explanation:

Price to Pay (P)

distance (m)

Company A

Pa = 0.80m

Company B

Pb = 65 + 0.01m

Company A charge more than B is written like this

0.8m > 65 + 0.01m

then we can solve this inequality

(0.8 - 0.01)m > 65

0.79m > 65

m > 65/0.79

m > 82.28 miles

so if Maya will go more than 82.28 miles, I suggest Company B is cheaper

Answer:

Step-by-step explanation:

The probability that a dentist recommend Colgate is;

P = 1/2 = 0.5

The probability that a dentist doesn't recommend Colgate is;

P' = 1 - P = 1 -0.5 = 0.5

Of 10 sample dentists, the probability that exactly 8 dentists recommend Colgate toothpaste is;

8 will recommend and two will not recommend it.

P(X) = P^8 × P'^2

P(X) = (0.5)^8 × (0.5)^2

P(X) = 0.0039 x 0.25

P(X) = 0.00098 = 0.098%

Answer:

f(x)= 4x or y=4x

Step-by-step explanation:

X represents minutes and the 4 is how many dishes she can wash.

Answer:

  1.504×10⁶ ft·lb

Step-by-step explanation:

We understand the top of the oil in the tank is 12 ft below ground level, and the bottom of the tank is 8+18=26 ft below ground level. Then the average depth of the oil is (12+26)/2 = 19 ft below ground level.

The height of the oil in the tank is 26-12=14 ft, so the volume of it is ...

  V = πr²h = π(6 ft)²(14 ft) = 504π ft³ ≈ 1583.36 ft³

__

So, the work required to raise that volume of oil to the surface is ...

  (1538.36 ft³)(50 lb/ft³)(19 ft) = 1.504×10⁶ ft·lb

Answer:

$900

Step-by-step explanation:

If she holds $500 and she is charged 15%; it means

The interest she pays per month is ;

$500 × 15/100 = $75

Then annually meaning for 12 months, she pays;

$75 × 12 = $900

Her annual interest on her current card is $900.

Therefore,

She will be taxed 15% if she holds $500, which means

The monthly interest she pays is;

$500 × 15/100 = $75

She then pays annually, which is for a full year;

$75 × 12 = $900

Hence, Her annual interest on her current card is $900.

To learn more about annual interest refer to:

brainly.com/question/20690803

#SPJ2

Answer:

$9400

Step-by-step explanation:

1.5x4=6%

100-6=94

0.94x10000=9400

Answer:

D

Step-by-step explanation:

3/40 * 2.5/2.5 = 7.5/100 = 0.075

Answer:

[tex] m=\frac{y_2 -y_1}{x_2 -x_1}[/tex]

And replacing we got:

[tex] m=\frac{1-(-3)}{3-(-3)}= \frac{4}{6}=\frac{2}{3}[/tex]

And we can use one of the points in order to find the intercept like this:

[tex] -3= \frac{2}{3} (-3) +b[/tex]

[tex] b =-3 +2=-1[/tex]

And the equation would be given by:

[tex] y= \frac{2}{3}x -1[/tex]

Step-by-step explanation:

We want an equation given by:

[tex] y=mx+b[/tex]

where m i the slope and b the intercept

We have the following two points given:

[tex] (x_1 = -3, y_1 =-3), (x_2=3, y_2 =1)[/tex]

We can find the slope with this formula:

[tex] m=\frac{y_2 -y_1}{x_2 -x_1}[/tex]

And replacing we got:

[tex] m=\frac{1-(-3)}{3-(-3)}= \frac{4}{6}=\frac{2}{3}[/tex]

And we can use one of the points in order to find the intercept like this:

[tex] -3= \frac{2}{3} (-3) +b[/tex]

[tex] b =-3 +2=-1[/tex]

And the equation would be given by:

[tex] y= \frac{2}{3}x -1[/tex]

Answer:

7000

Step-by-step explanation:

If the hundreds place is higher than 5, then add 1 to the thousands place.

Answer:

D

Step-by-step explanation:

If <CAD=35, <KNL=55 because the remaining angle is 90 since it's a right angle. Therefore <KNM=110 because 55+55=110

Answer:

m = - 5

Step-by-step Explanation:

[tex]-3(1-5m)=-38+8m \\ \\ - 3 + 15m = - 38 + 8m \\ \\ 15m - 8m = 3 - 38 \\ \\ 7m = - 35 \\ \\ m = \frac{ - 35}{7} \\ \\ \huge \purple{ \boxed{m = - 5}}[/tex]

Answer:

-5

Step-by-step explanation:

1) sorry i don't know =(

2)- 5/12 is the simplified fraction for 60/144.

3)A=54cm²

Answer:

[tex]P(x>20)=9.67*10^{-10}[/tex]

Step-by-step explanation:

If we call x the number of correct answers, we can said that P(x) follows a Binomial distribution, because we have 25 questions that are identical and independent events with a probability of 1/4 to success and a probability of 3/4 to fail.

So, the probability can be calculated as:

[tex]P(x)=nCx*p^{x}*q^{n-x}=25Cx*0.25^{x}*0.75^{25-x}[/tex]

Where n is 25 questions, p is the probability to success or 0.25 and q is the probability to fail or 0.75.

Additionally, [tex]25Cx=\frac{25!}{x!(25-x)!}[/tex]

So, the probability that the student answers more than 20 questions correctly is equal to:

[tex]P(x>20)=P(21)+P(22)+P(23)+P(24)+P(25)[/tex]

Where, for example, P(21) is equal to:

[tex]P(21)=25C21*0.25^{21}*0.75^{25-21}=9.1*10^{-10}[/tex]

Finally, P(x>20) is equal to:

[tex]P(x>20)=9.67*10^{-10}[/tex]