Practice variation 1 of 3
Binomial distribution — p=0.4, n=400
Your question
A population has proportion . A random sample of size is taken and is the sample proportion.
(i) Show that .
(ii) Hence use the standard normal distribution to approximate , giving your answer correct to two decimal places.
This practice question was inspired by Question 11(f) in the 2023 NSW HSC Mathematics Extension 1 examination, © NESA. It is an original TestMum variation that practises the same mathematical idea, not an official NESA question.
Before you check
- Have you stated every choice or assumption?
- Can another student follow each line?
- Did you verify the final result independently?