STAT Chapter 10

3. In a study about how well students understand instructions, a group of 12 student volunteers were given two comparable tasks to perform. For one of the tasks, each student received written instructions. For the other task, the student received verbal instructions from a recorded voice. The order of the method of instruction was randomized. The performance of each student was rated on a scale from 1 to ill]. The data is shown below. manna ---------IEIEIEI -------- [a] [1 pt] Calculate the mean difference [written - audio] in performance and the standard deviation of the differences in performance. Interpret the standard deviation. [b] [-1- pts] Construct and interpret a 95% condence interval for the true mean difference [written