Question

If n=600 and ˆp=0.1, construct a 95% confidence interval about the population proportion. ROUND ANSWER TO THREE DECIMAL!

Preliminary:

1. Is it safe to assume that n≤0.05 of all subjects in the population?
   • Yes
   • No
   
   
2. Verify nˆp(1−ˆp)≥10 = ? ROUND ANSWER TO ONE DECIMAL.
   
   3. nˆp(1−ˆp)= ?

4. Confidence Interval: What is the 95% confidence interval to estimate the population proportion? ROUND ANSWER TO 3 DECIMAL PLACES!!!!!

5. ??????? < p < ???

Answer 1

Yes, n <= 0.05 N

n ( 1 - ) = 600 * 0.1 * ( 1 - 0.1) = 54 >= 10

95% confidence interval for p is

- Z* sqrt [ ( 1 - ) / n ] < p < + Z* sqrt [ ( 1 - ) / n ]

0.1 - 1.96 * sqrt [ 0.1 * ( 1 - 0.1) / 600] < p < 0.1 + 1.96 * sqrt [ 0.1 * ( 1 - 0.1) / 600]

0.076 < p < 0.124