Question

Based on historical data, your manager believes that 27% of the company's orders come from first-time customers. A random sample of 152 orders will be used to estimate the proportion of first-time-customers. What is the probability that the sample proportion is less than 0.33?

Answer 1

Solution :

Given that ,

p = 0.27

1 - p = 0.73

n = 152

= p = 0.27  

= (p*(1-p))/n =  (0.27*0.73)/ 152= 0.0360

P( < 0.33) = P(( - ) / < (0.33 - 0.27) / 0.0360)

= P(z < 1.67)

= 0.9525

Probability = 0.9525