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
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the z-score that has a p-value of
.
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 
95% confidence level
So
, z is the value of Z that has a p-value of
, so
.
The lower limit of this interval is:

The upper limit of this interval is:

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).
Answer:
x = ± 4
Step-by-step explanation:
given 3x² = 48 ( divide both sides by 3 )
x² = 16 ( take the square root of both sides )
x = ±
= ± 4
x ∈ {- 4, 4 }
Ratio 10:6
so 10+6 = 16
112/16 =7
white balls: 10 * 7 = 70
striped balls: 6 * 7 = 42
Answer: he needs to add 70 white balls and 42 striped balls to keep the same ratio 10:6
You are not giving enough information but in one of the calsses the average of student's height might be greater than the other class beacause one of the two classes needs to have 1 extra person than the other calss
Yes he is correct because if you do the algorithm, 0+3=3 and 20+40=60 and 60+3=63. There is no regrouping needed.