Question

Find the minimum sample size n needed to estimate μ For the given values of​ c, σ​, and E. c=0.98 σ=8.7,and E=2 Assume that a preliminary sample has at least 30 members. n= Round up to the nearest whole​ number.)

Answer 1

Solution:

Given ,

= 8.7 ..Population SD

E = 2 Margin of error

c = 98% = 0.98 ...confidence level

= 1- c = 1- 0.98 = 0.02

  /2 = 0.01

Using Z table ,

= 2.326

Now, sample size (n) is given by,

=  {(2.326* 8.7)/ 2 }2

= 102.4

= 103 ..(round to the next whole number)

n = 103