Answer:
The median is marked at 161cm instead of 162cm.
The right part of the box (the upper quartile) is marked at 172cm, while the interquartile range is 17cm, so the upper quartile should be at 154cm + 17cm = 171cm.
It is 4pi/7, or b. Just want to help ;)
Take the root of both sides, and solve.
x = 2i sqrt 2, -2i sqrt 2.
Answer:
b. It will decrease by a factor of 2
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence interval
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of
.
The lower end of the interval is given by:

The upper end of the interval is given by:

The length of the interval is the subtraction of the upper end by the lower end, so it is:

This means that the length is inverse proportional to the square root of the size of the sample.
So, if the sample size is multiplied by 4, the length of the interval is going to decrease by a factor of 2.