<span>To find the z-scores, find the difference in the number of inches for each value from the mean and then divide that by the standard deviation. For women at 72 inches (6'), this would be (72-64) / 2.7, or a z-score of +2.963. For a male at 72 inches, this would be (72-69.3)/2.8, or +0.964. This shows that the woman at 6 feet tall is more rare in the distribution than a man at 6 feet tall.</span>
Answer:
We need a sample size of least 119
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 zscore that has a pvalue of
.
The margin of error is:

95% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
Sample size needed
At least n, in which n is found when 
We don't know the proportion, so we use
, which is when we would need the largest sample size.






Rounding up
We need a sample size of least 119
Step-by-step explanation:
<u>Using Pythagorus theorem</u> :
(A)


(B)
