A group of 5 statistics students receive the following grades on a test: 81, 74, 62, 92, and 76 ...

     A group of   5 statistics students receive the following grades on a test: 81, 74, 62, 92,   and 76. An intervention plan is used and the students increased their scores   on a retest to: 85, 79, 75, 95 and 84. At the 0.05 significance level, is the   intervention plan helpful in increasing the grades?