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In: Statistics and Probability

Claim: The average cost to repair washing machine A is the same as the average cost...

Claim: The average cost to repair washing machine A is the same as the average cost to repair washing machine B. Test at α = 0.1 Data: A sample of 24 washing machine A’s have an average repair cost of $208 and a standard deviation of $22. A sample of 26 washing machine B’s have an average repair cost of $221 and a standard deviation of $19. Assume that the population standard deviations for repair costs are the same for each (a) Are these data statistically significant evidence to support the claim? (b) Are these data statistically significant evidence to refute the claim?

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