You must substitute the (x, y) and check that the POI makes both equations __

An athletics coach states that the distribution of player run times (in seconds) for a 100-meter dash is normally distributed wi

Elza [17]

Answer:

$P(X$

And we can find this probability using the normal standard distribution table and we got:

$P(z$

And the percentage faster than 13.28 seconds would be 91.9%

Step-by-step explanation:

Let X the random variable that represent the runtimes of a population, and for this case we know the distribution for X is given by:

$X \sim N(13,0.2)$

Where $\mu=13$ and $\sigma=0.2$

We want to find this probability:

$P(X$

And we can use the z score formula given by:

$z=\frac{x-\mu}{\sigma}$

Using this formula we have:

$P(X$

And we can find this probability using the normal standard distribution table and we got:

$P(z$

And the percentage faster than 13.28 seconds would be 91.9%

8 0

3 years ago

Please answer this question and i will mark you brainliest.

juin [17]

Answer:

4 altogether

0,1 + 1, 1 = 1 RA

0,1 + 2,1 = 1 RA

0.2 +1, 2 = 1 RA

0,2 +2,2 = 1 RA

Step-by-step explanation:

8 0

3 years ago

Toll Brothers is a luxury home builder that would like to test the hypothesis that the average size of new homes exceeds 2,400 s

boyakko [2]

Answer:

Since the pvalue of the test is 0.09 > 0.01, we do not reject the null hypothesis that the average size of new homes is of 2400 square feet.

Step-by-step explanation:

Toll Brothers is a luxury home builder that would like to test the hypothesis that the average size of new homes exceeds 2,400 square feet. Test to see if the average size of new homes exceeds 2,400 square feet.

At the null hypothesis, we test if the average is of 2400 square feet, that is:

$H_o: \mu = 2400$

At the alternate hypothesis, we test if the average is greater than 2400 square feet, that is:

$H_a: \mu > 2400$

The test statistic is:

Since we have the standard deviation for the sample, we use the t-distribution.

$t = \frac{X - \mu}{\frac{s}{\sqrt{n}}}$

In which X is the sample mean, $\mu$ is the value tested at the null hypothesis, s is the standard deviation of the sample and n is the size of the sample.

2400 is tested at the null hypothesis:

This means that $\mu = 2400$

A random sample of 36 newly constructed homes had an average of 2,510 square feet with a sample standard deviation of 480 square feet.

This means that $n = 36, X = 2510, s = 480$

Test statistic:

$t = \frac{X - \mu}{\frac{s}{\sqrt{n}}}$

$t = \frac{2510 - 2400}{\frac{480}{\sqrt{36}}}$

$t = 1.375$

Pvalue of the test and decision:

The pvalue of the test is the probability of finding a sample mean of at least 2510, which is the pvalue of t = 1.375 with 36 - 1 = 35 degrees of freedom, using a one-tailed test.

With the help of a calculator, this pvalue is of 0.09

Since the pvalue of the test is 0.09 > 0.01, we do not reject the null hypothesis that the average size of new homes is of 2400 square feet.

6 0

3 years ago

“The 7th grade class is planning a pancake breakfast. All materials are donated except the pancake mix. Based on the given infor

ArbitrLikvidat [17]

Answer:

a) 720

b) 60$

Step-by-step explanation:

a) each person is served 3 pancakes and there are 240 people, 240 x 3 = 720.

b) Each bag of mix costs 10$ and can make 120 pancakes, but we need 720 pancakes, which means six bags of mix (since 120x6 = 720). Since each cost 10$, 10 x 6 = 60$

6 0

3 years ago

A video posted on the internet has gone viral, and the total number of views is increasing by 25% every hour. If the video curre

sergeinik [125]

$\qquad \textit{Amount for Exponential Growth} \\\\ A=P(1 + r)^t\qquad \begin{cases} A=\textit{accumulated amount}\\ P=\textit{initial amount}\dotfill &155000\\ r=rate\to 25\%\to \frac{25}{100}\dotfill &0.25\\ t=hours\dotfill &6\\ \end{cases} \\\\\\ A=155000(1 + 0.25)^{6}\implies A=155000(1.25)^6\implies A\approx 591278$

8 0

2 years ago

You must substitute the (x, y) and check that the POI makes both equations ___.