Question

ASAP

If n=180 and p' (p-prime) = 0.2, construct a 99% confidence interval.

Give your answers to three decimals.

< p <

Answer 1

Solution :

Given that,

Point estimate = sample proportion = = 0.2

Z_/2 = 2.576

Margin of error = E = Z _{/ 2} * (( * (1 - )) / n)

= 2.576 * (((0.2 * 0.8) / 180)

= 0.077

A 99% confidence interval for population proportion p is ,

- E < p < + E

0.2 - 0.077 < p < 0.2 + 0.077

0.123 < p < 0.277