Question

In: Statistics and Probability

The mean age of a random sample of 25 people who were playing the slot machines...

The mean age of a random sample of 25 people who were playing the slot machines is 55.3 years and the standard deviation is 6.8 years. The mean age of a random sample of 35 people who were playing roulette is 49.7 years with a standard deviation of 4.2 years.
1. Find the 99% confidence interval of the true difference in means.
1. Would you reject the null hypothesis that there is no difference in the mean ages of slot machine players and roulette players? Justify.

Expert Solution

To Test :-

H0 :-

H1 :-

Test Statistic :-

t = 3.6502

Test Criteria :-
Reject null hypothesis if

DF = 36

Result :- Reject Null Hypothesis

Decision based on P value
P - value = P ( t > 3.6502 ) = 0.0008
Reject null hypothesis if P value < level of significance
P - value = 0.0008 < 0.01 ,hence we reject null hypothesis
Conclusion :- Reject null hypothesis

Confidence interval :-

Lower Limit =
Lower Limit = 1.4279
Upper Limit =
Upper Limit = 9.7721
99% Confidence interval is ( 1.4279 , 9.7721 )

orchestra answered 2 years ago

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