Answer:
The sample size 'n' = 26
Step-by-step explanation:
Explanation:-
Given a researcher wishes to estimate within $5 the average repair cost of for a refrigerator
Given estimate "E" = $5
The estimate within the average is determined by
[tex]E = \frac{Z_{0.10}S.D }{\sqrt{n} }[/tex]
Level of significance ∝ = 90 % or 10%
= 0.90 or o.10
Z₀.₁₀ = 1.645
[tex]E = \frac{Z_{0.10}S.D }{\sqrt{n} }[/tex]
[tex]5 = \frac{1.645 X15.50 }{\sqrt{n} }[/tex]
√n = [tex]\frac{25.49}{5} = 5.099[/tex]
Squaring on both sides , we get
n = 26
Conclusion:-
The sample size 'n' = 26
