Question

People were polled on how many books they read the previous year. How many subjects are needed to estimate the number of books read the previous year within one book with 99​% ​confidence? Initial survey results indicate that o= 13.6 books.

Answer 1

Solution :

Given that,

  = 13.6

E = 1

At 99% confidence level the z is ,

  = 1 - 99% = 1 - 0.99 = 0.01

/ 2 = 0.01 / 2 = 0.005

Z_/2 = Z_0.005 = 2.576

sample size = n = (Z_/2* /E)2

n = (2.576 * 13.6 / 1)2

n= 1227