In a survey of 162 publiclytraded companies the average pric

In a survey of 162 publicly-traded companies, the average price-earnings ratio was 18.3 with a standard deviation of 9.2. When testing the hypothesis (at the 5% level of significance) that the average energy use has decreased from the past value of 16.4, what is the test statistic? (please round your answer to 2 decimal places)

Solution

what is the test statistic?

t = [ 16.4 - 18.3 ] / [ 9.2 / srqt(162) ]

t = -1.9 / 0.7228

t = -2.63