Using the z-distribution, it is found that the 95% confidence interval for the proportion of sales that occured in December is (0.1648, 0.2948).

<h3>What is a confidence interval of proportions?</h3>

A confidence interval of proportions is given by:

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which:

$\pi$ is the sample proportion.

z is the critical value.

n is the sample size.

In this problem, we have a 95% confidence level, hence $\alpha = 0.95$ , z is the value of Z that has a p-value of $\frac{1+0.95}{2} = 0.975$ , so the critical value is z = 1.96.

The sample size and the estimate are given by:

$n = 161, \pi = \frac{37}{161} = 0.2298$

Hence:

$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.2298 - 1.96\sqrt{\frac{0.2298(0.7702)}{161}} = 0.1648$

$\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.2298 + 1.96\sqrt{\frac{0.2298(0.7702)}{161}} = 0.2948$

The 95% confidence interval for the proportion of sales that occured in December is (0.1648, 0.2948).

More can be learned about the z-distribution at brainly.com/question/25890103

5 0

2 years ago

What is the slope of a line parallel to line B?

Aleksandr [31]

When the lines are parallel, the slope have to be the same for both and we know that the slope of line B is 5/2, so the answer would be D) 5/2

6 0

3 years ago

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The 200 students in a school band will attend and awards dinner. A random survey of 25 of these students was conducted to determ

vagabundo [1.1K]

C, there are 32 more students who want a beef meal than want a chicken meal.

200/25 = 8
12 x 8 = 96
8 x 8 = 64
5 x 8 = 40
& 96 - 64 = 32

5 0

2 years ago