Question

Chapter 6, Section 2-CI, Exercise 111 What Influences the Sample Size Needed? In this exercise, we examine the effect of the value of the estimated standard deviation on determining the sample size needed Find the sample size needed to give, with % confidence, a margin o error within 5 if the estimated standard de ation sơ-: fthe estimate standard deviation so-s the esti mate standard deviation is Ơ 10. Round your answers up to the nearest integer. 8-40:n o 20

Answer 1

1)

~ 40

Sample Size is

2(2.58 402 = (쯤). (2.ssu)- Zo rl 426.0096 426

b) When $\widetilde{\sigma } = 20$

The Sample size is

22.58 202 rl 106.5024107

c) When $\widetilde{\sigma } = 10$

The Sample Size is

= (쯤)'= (258,10),- Zo rl 26.6256 27