Question

Suppose that a company would like a 0.95 probability that the sample proportion of all adults who would never give personal data to a company is within 0.1 of the population proportion.

How large a sample size is needed to meet the required precision? Assume that the previous sample of similar units yielded 0.2 for the sample proportion.

	a.	6.14
	b.	31.36
	c.	61.4

A fashion designer would like to know how many new dresses women buy each year. She thinks the mean is 5.1 dresses per year. Assume a previous study found the standard deviation of the population to be 1.8. How large a sample would be required in order to estimate the mean number of dresses bought per woman at the 95% confidence level with an error of at most 0.12 dresses?

Determine the sample size:

	a.	480.20
	b.	864.36
	c.	103.72

Answer 1

Solution:

1)

2)