X (number of hours) 1 2 3 4 y (earnings in dollars) 8 20 32 44

A store randomly samples 603 shoppers over the course of a year and finds that 142 of them made their visit because of a coupon

fiasKO [112]

Answer:

The 95% confidence interval for the fraction of all shoppers during the year whose visit was because of a coupon they'd received in the mail is (0.2016, 0.2694).

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

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

In which

z is the z-score that has a p-value of $1 - \frac{\alpha}{2}$ .

A store randomly samples 603 shoppers over the course of a year and finds that 142 of them made their visit because of a coupon they'd received in the mail.

This means that $n = 603, \pi = \frac{142}{603} = 0.2355$

95% confidence level

So $\alpha = 0.05$ , z is the value of Z that has a p-value of $1 - \frac{0.05}{2} = 0.975$ , so $Z = 1.96$ .

The lower limit of this interval is:

$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.2355 - 1.96\sqrt{\frac{0.2355*0.7645}{603}} = 0.2016$

The upper limit of this interval is:

$\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.2355 + 1.96\sqrt{\frac{0.2355*0.7645}{603}} = 0.2694$

The 95% confidence interval for the fraction of all shoppers during the year whose visit was because of a coupon they'd received in the mail is (0.2016, 0.2694).

8 0

1 year ago

136mm into cm and mm

Alex Ar [27]

Step-by-step explanation:

13.6 is the answer because 1cm is 10 cm

4 0

1 year ago

Read 2 more answers

The Floyds have considered three options to ensure they have at least $1,375 saved for their trip.

ANTONII [103]

I am guessing you are talking about Option 3. They start with $125. So they times it by 1.25 as we are using the multiplier method. So in the First month, it will be 156.25. Second it will be 195.3125. So in August it will be $476.837157. Of couse round it and you will get $476.84.

I believe there is a more efficent way of doing this but I have forgotten.

4 0

2 years ago

Pls I need the answer and explanasion

Y_Kistochka [10]

Answer:

=no of children who like oatmeal/toatal population*100%

=15/50*100%

=(1500/50)%

=30%

Step-by-step explanation:

3 0