Answer:
Confidence interval is 0.7 ≤ p ≤ 0.8
The margin of error is 7.1 %
Step-by-step explanation:
We have to calculate a 98% confidence interval for the proportion.
The sample proportion is p=0.75.
The standard error of the proportion is:
Here we have, the proportion or point estimate given by
= 150/200 = 0.75
Sample size, n = 200
The formula for confidence interval, CI, given a proportion, is;
At 98% z = ±2.326348
Plugging in the values of, , z and n we get;
CI = 0.6787704 ≤ p ≤ 0.8212296
To one decimal place, we have
CI = 0.7 ≤ p ≤ 0.8