At least 350 students attended the band concert friday night

A student placement center has request from six students for interviews regarding employment with a particular consulting firm,

Nikolay [14]

Use the image below for your answer please

3 0

2 years ago

The Information Technology Department at a large university wishes to estimate the proportion of students living in the dormitor

nadya68 [22]

Answer:

$n=\frac{0.5(1-0.5)}{(\frac{0.05}{1.96})^2}=384.16$

And rounded up we have that n=385

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

Solution to the problem

In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 99% of confidence, our significance level would be given by $\alpha=1-0.99=0.01$ and $\alpha/2 =0.005$ . And the critical value would be given by:

$z_{\alpha/2}=-2.58, z_{1-\alpha/2}=2.58$

The margin of error for the proportion interval is given by this formula:

$ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}$ (a)

And on this case we have that $ME =\pm 0.05$ and we are interested in order to find the value of n, if we solve n from equation (a) we got:

$n=\frac{\hat p (1-\hat p)}{(\frac{ME}{z})^2}$ (b)

We can use as an estimator for p $\hat p =0.5$ . And replacing into equation (b) the values from part a we got:

$n=\frac{0.5(1-0.5)}{(\frac{0.05}{1.96})^2}=384.16$

And rounded up we have that n=385

3 0

2 years ago

Find tan(B) in the triangle. Choose 1 answer A 15/8 B 8/17 C 8/15 D 15/17

erastova [34]

Answer: C
Explanation: tan = opposite/adjacent. 8 is the opposite length from angle B and 15 is the adjacent length from angle B. so tan(B) = 8/15

6 0

2 years ago

Read 2 more answers

Andrew and Sam start counting from 150 to 200 including. Andrew counts by fives, and Sam counts by threes. What is the ratio of

Agata [3.3K]

Answer:

11/17

Step-by-step explanation:

The question says to find the ratio by which Andrew counts to the ratio Sam counts.

Andrew counts by 5s:

150,155,160,165,170,175,180,185,190,195,200. His total count is 11

Sam counts by 3s:

150,153,156,159,162,165,168,171,174,177,180,183,186,189,192,195,198. His total number of count is 17

The ratio of their count is 11:17

= 11/17

3 0

3 years ago

Read 2 more answers

In isosceles pqr with base , pq = 2x + 3, and pr = 9x - 11. what is the value of x?

Anon25 [30]

First, draw and label a rough sketch of an isosceles triangle. Now put in the values of pq=2x+3 and pr=9x-11

You know that the triangle is isosceles, therefore, the sides pq and pr are identical.

Now, make the equations equal to each other to find the value of x.

2x+3=9x-11
3+11=9x-2x
14=7x
14/7=x
2=x

Therefore the value of x=2.

Hope I helped :)

8 0

2 years ago