Scaled

Mathematics Methods · Unit 4 · Topic 4.3

Interval estimates for proportions

5 free questions, 2 calculator-free and 3 calculator-assumed, with worked solutions written like marking keys.

Calculator-freefoundation

In a random sample of 200200 voters, 8080 support a proposal. Determine the sample proportion p^\hat{p}.

Calculator-assumedstandard

For samples of size n=100n = 100 from a population with p=0.5p = 0.5, determine the standard deviation of the sample proportion p^\hat{p}.

Calculator-freefoundation

For samples of size n=400n = 400 from a population with p=0.2p = 0.2, state the mean of the sample proportion p^\hat{p}.

Calculator-assumedstandard

For samples of size n=64n = 64 from a population with p=0.25p = 0.25, determine the standard deviation of p^\hat{p}.

Calculator-assumedstandard

A sample of 400400 gives p^=0.5\hat{p} = 0.5. Determine the margin of error for a 95%95\% confidence interval, using z=1.96z = 1.96, correct to four decimal places.