A supervisor of a textile industry collected information regarding the mean number of hours of productive work done by a random sample of ten workers in a month. After the performance bonus was announced by the management, the supervisor again collected the information on the mean number of hours of productive work done by the same ten workers in the next month. The results are summarized below: Worker Before bonus After bonus 1 7.1 6.5 2 6.5 7.5 3 17.5 17.3 4 6.7 6.7 5 6.4 6.9 6 17.3 17.3 7 6.9 6.9 Construct a 99% confidence interval for the difference in the mean number of hours of productive work done by the workers in the month before and after the announcement of the bonus.
Added by Alejandro K.
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Calculate the difference in hours for each worker (After bonus - Before bonus). Show more…
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