Question

A social psychologist wants to know whether students' performance on a problem solving task is lowered by having other people look on when completing the task. She randomly selects 22 students and has them complete the task with onlookers and finds that their mean score on the problem solving task equals 67.9 with variance equal to 108.2. Scores on the problem solving task for the population of students who complete the task without onlookers are distributed normally with a mean equal to 66 . Is there sufficient evidence to conclude that performance on the problem solving task is lowered by having onlookers? Use a significance level of 0.01

Step 1 of 5 :  

State the Null and Alternative Hypotheses for this scenario.

Answer 1

Step 1 of 5 :

null hypothesis:		μ	>=	66
Alternate Hypothesis:		μ	<	66

standard errror of mean =	sx=s/√n=	2.2177
test statistic          t              =	(x-μ)/sx=	0.857

critical value : -2.518 , therefore reject Ho if t < -2.518

p value =0.2006

fail to reject Ho

( please reply if help is required in any other steps of above)