Martha and steve have 95 colored pencils. If Martha has 4 times as many as steve, how many does Steve have

A fuel oil tank is an upright cylinder, buried so that its circular top 12 feet beneath ground level. The tank has a radius of 6

Anuta_ua [19.1K]

I end up with 625pi(27^2-14^2)

=635pi(504)

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2 years ago

Maridel wants to find out how many of her classmates plan to come to the next football game. There are 800 students in her schoo

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Answer:

Maridel wants to find out how many of her classmates plan to come to the next football game. There are 800 students in her school. She selects a sample of the population by putting the names of every student into a bag and drawing out 100 names.

Which statement(s) describe her sampling method? Check all that apply.

A) Her method will produce a biased sample.

B) Her method will produce a valid sample.

C) Her method will produce a random sample.

D) Her method will produce a representative sample.

E) Her method will produce an invalid sample.

Step-by-step explanation:

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Point A has coordinates (7,2). Point B has coordinates (2,-10). Find the coordinates of point P that partition AB in the ratio o

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You have to use section formula for internal division.

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The results of a mathematics placement exam at two different campuses of Mercy College follow: Campus Sample Size Sample Mean Po

Leona [35]

Answer:

$z=\frac{(33-31)-0}{\sqrt{\frac{8^2}{330}+\frac{7^2}{310}}}}=3.37$

$p_v =P(Z>3.37)=1-P(Z$

Comparing the p value with a significance level for example $\alpha=0.05$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and we can say that the mean for the Campus 1 is significantly higher than the mean for the group 2.

Step-by-step explanation:

Data given

Campus Sample size Mean Population deviation

1 330 33 8

2 310 31 7

$\bar X_{1}=33$ represent the mean for sample 1

$\bar X_{2}=31$ represent the mean for sample 2

$\sigma_{1}=8$ represent the population standard deviation for 1

$\sigma_{2}=7$ represent the population standard deviation for 2

$n_{1}=330$ sample size for the group 1

$n_{2}=310$ sample size for the group 2

$\alpha$ Significance level provided

z would represent the statistic (variable of interest)

Concepts and formulas to use

We need to conduct a hypothesis in order to check if the mean for Campus 1 is higher than the mean for Campus 2, the system of hypothesis would be:

Null hypothesis: $\mu_{1}-\mu_{2}\leq 0$

Alternative hypothesis: $\mu_{1} - \mu_{2}> 0$

We have the population standard deviation's, and the sample sizes are large enough we can apply a z test to compare means, and the statistic is given by:

$z=\frac{(\bar X_{1}-\bar X_{2})-\Delta}{\sqrt{\frac{\sigma^2_{1}}{n_{1}}+\frac{\sigma^2_{2}}{n_{2}}}}$ (1)

z-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.

With the info given we can replace in formula (1) like this:

$z=\frac{(33-31)-0}{\sqrt{\frac{8^2}{330}+\frac{7^2}{310}}}}=3.37$

P value

Since is a one right tailed test the p value would be:

$p_v =P(Z>3.37)=1-P(Z$

Comparing the p value with a significance level for example $\alpha=0.05$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and we can say that the mean for the Campus 1 is significantly higher than the mean for the group 2.

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A person places $934 in an investment account earning an annual rate of 6.1%, compounded continuously. Using the formula V = P n

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Yes man yes we are here for dinner last night

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