Statistics-computing the z-statistic

Assignment Help Basic Statistics

Reference no: EM13113302

An automobile assembly line operation has a scheduled mean completion time,u , of 12.6 minutes. The standard deviation of completion times is 1.8 minutes. It is claimed that, under new management, the mean completion time has decreased. To test this claim, a random sample of 48 completion times under new management was taken. The sample had a mean of 12.5 minutes. Assume that the population is normally distributed. Can we support, at the 0.1 level of significance, the claim that the mean completion time has decreased under new management? Assume that the standard deviation of completion times has not changed.

Perform a one-tailed test. Then fill in the table below.

The null hypotheses is:

The alternative hypothesis is:

Type of test statistic:

The value of the test statistic (round to at least three decimal places):

The p-value (round to at least three decimal places):

Can we support the claim that the mean completion time has decreased under new management?

Reference no: EM13113302

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