Question

Based on historical data, AGECEAT finds that 80% of the orders were delivered
within 30 minutes. Last week AGECEAT received 250 orders and 190 of the
ordered were delivered within 30 minutes.
A. Calculate the proportion of orders delivered within 30 minutes based on the
sample obtained last week.
B. Under what conditions can we use normal distribution to approximate the
distribution of sample proportion with a sample size of 250? Verify if these
conditions hold.
C. What is the distribution of sample proportion with a sample size of 250?
D. Find the probability that a sample of size 250 would produce a sample
proportion so low as was observed in this sample.

Answer 1