Question

Mob Boss Sammy the Bull claims his hit men require, on average, no more than 6 shots to ice their target. A sample of 40 hits reveals a mean of 6.5 shots with standard deviation of 1.7. At LC=93%, is his claim true.

Answer 1

H0: <= 6

Ha: > 6

Test Statistic :-
t = ( X̅ - µ ) / (S / √(n) )
t = ( 6.5 - 6 ) / ( 1.7 / √(40) )
t = 1.86

Test Criteria :-
Reject null hypothesis if t > t(α, n-1)
Critical value t(α, n-1) = t(0.07 , 40-1) = 1.506

t > t(α, n-1) = 1.86 > 1.506
Result :- Reject null hypothesis

We reject the claim that hit men require, on average, no more than 6 shots to ice their target.