Officials in charge of televising an international chess competition in South America want to determine if the average time per move for the top players has remained at 4 minutes over the last two years. Video tapes of matches which have been played over the two-year period are reviewed and a random sample of 47 moves are timed. The sample mean is 3.5 minutes. Assume the population standard deviation is 3.3 minutes. Using the confidence interval approach, test the hypothesis that the average time per move is different from 4 minutes at a 0.02 significance level. Step 1 of 2 : Calculate a confidence interval for the average time per move. Round your answers to two decimal places.

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