There are 99 males and 121 females participating in a marathon. What participants are females?

A sample of 100 workers located in Atlanta has an average daily work time of 6.5 hours with a standard deviation of 0.5 hours. A

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Answer:

$t=\frac{6.5-6.7}{\sqrt{\frac{0.5^2}{100}+\frac{0.7^2}{110}}}}=-2.398$

$df = n_1 +n_2 -2= 100+110-2= 208$

Since is a bilateral test the p value would be:

$p_v =2*P(t_{208}$

Comparing the p value with the significance level given $\alpha=0.05$ we see that $p_v$ so we can conclude that we can reject the null hypothesis, and we have significant differences between the two groups at 5% of significance.

Step-by-step explanation:

Data given and notation

$\bar X_{1}=6.5$ represent the sample mean for Atlanta

$\bar X_{2}=6.7$ represent the sample mean for Chicago

$s_{1}=0.5$ represent the sample deviation for Atlanta

$s_{2}=0.7$ represent the sample standard deviation for Chicago

$n_{1}=100$ sample size for the group Atlanta

$n_{2}=110$ sample size for the group Chicago

t would represent the statistic (variable of interest)

$\alpha=0.01$ significance level provided

Develop the null and alternative hypotheses for this study?

We need to conduct a hypothesis in order to check if the meanfor atlanta is different from the mean of Chicago, the system of hypothesis would be:

Null hypothesis: $\mu_{1}=\mu_{2}$

Alternative hypothesis: $\mu_{1} \neq \mu_{2}$

Since we don't know the population deviations for each group, for this case is better apply a t test to compare means, and the statistic is given by:

$t=\frac{\bar X_{1}-\bar X_{2}}{\sqrt{\frac{s^2_{1}}{n_{1}}+\frac{s^2_{2}}{n_{2}}}}$ (1)

t-test: Is used to compare group means. Is one of the most common tests and is used to determine whether the means of two groups are equal to each other.

Calculate the value of the test statistic for this hypothesis testing.

Since we have all the values we can replace in formula (1) like this:

$t=\frac{6.5-6.7}{\sqrt{\frac{0.5^2}{100}+\frac{0.7^2}{110}}}}=-2.398$

What is the p-value for this hypothesis test?

The degrees of freedom are given by:

$df = n_1 +n_2 -2= 100+110-2= 208$

Since is a bilateral test the p value would be:

$p_v =2*P(t_{208}$

Based on the p-value, what is your conclusion?

Comparing the p value with the significance level given $\alpha=0.05$ we see that $p_v$ so we can conclude that we can reject the null hypothesis, and we have significant differences between the two groups at 5% of significance.

3 0

3 years ago

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Q supp r and m q =22 degrees

netineya [11]

Answer:

<R = 158

Step-by-step explanation:

Supplementary angles equal 180 degrees.

<Q + <R =180

22 + <R = 180

Subtract 22 from each side

22-22 + <R = 180-22

R = 158

3 0

3 years ago

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You are constructing a tangent line from a point outside a given circle to the circle is to draw a circle and a point outside th

Alja [10]

I think its C I am not sure hope it helps

6 0

3 years ago

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One year Perry had the lowest ERA (earned-run average, mean number of runs yielded per nine innings pitched) of any male pitch

Blizzard [7]

Answer:

z score Perry $z=-1.402$

z score Alice $z=-1.722$

Alice had better year in comparison with Perry.

Step-by-step explanation:

Consider the provided information.

One year Perry had the lowest ERA of any male pitcher at his school, with an ERA of 3.02. For the males, the mean ERA was 4.206 and the standard deviation was 0.846.

To find z score use the formula.

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

Here μ=4.206 and σ=0.846

$z=\frac{3.02-4.206}{0.846}$

$z=\frac{-1.186}{0.846}$

$z=-1.402$

Alice had the lowest ERA of any female pitcher at the school with an ERA of 3.16. For the females, the mean ERA was 4.519 and the standard deviation was 0.789.

Find the z score

where μ=4.519 and σ=0.789

$z=\frac{3.16-4.519 }{0.789}$

$z=\frac{-1.359}{0.789}$

$z=-1.722$

The Perry had an ERA with a z-score is –1.402. The Alice had an ERA with a z-score is –1.722.

It is clear that the z-score value for Perry is greater than the z-score value for Alice. This indicates that Alice had better year in comparison with Perry.

7 0

3 years ago

Solve for h<br> Give an exact answer.<br> 3h=7( 2/7− 3/7 h)−10

romanna [79]

Its -4/3
Thank You.
Pls mark Brainliest!

6 0

3 years ago