A manufacturer claims that a new design for a phone has incr

A manufacturer claims that a new design for a phone has increased the range to 150 ft. An independent testing lab found that a random sample of 14 phones worked on average of 142 feet feet. What is the appropriate test statistic?

Solution

Hi!

If this is the only given, then it is not asking you to compute, because there is no standard deviation.

It is simply asking what kind of distribution you would use.

In that case, the answer is: T STATISTIC. [ANSWER]

Why?

This is because we have a small sample (n = 14 < 30), and we also do not know the population standard deviation. So we use the t distribution.

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If there are actually other givens, please resubmit this question together with the standard deviation (we need it to compute) or any other data that will lead to it. Thanks!