Question

How to answer this question

Answer 1

Answer:

(0.3049 ; 0.3751)

Step-by-step explanation:

The confidence interval for proportion can be obtained using the relation :

Phat ± Zcritical * [√phat(1-phat) / n]

phat = x / n

Sample size, n = 700

x = 238

phat = 238/700 = 0.34

Zcritical at 95% = 1.96

C.I = 0.34 ± 1.96 * [√0.34(1-0.34) / 700]

C.I = 0.34 ± 1.96 * 0.0179045

C. I = 0.34 ± 0.0350928

Lower boundary = 0.34 - 0.0350928 = 0.3049

Upper boundary = 0.34 + 0.0350928 = 0.37509

(0.3049 ; 0.3751)