What is the mean absolute deviation of the data: 8, 10, 15, 8, 12, 13, 12 and 14?​

Write the pair of fractions as a pair of fractions with a common denominator

3.17 scores on stats final. below are final exam scores of 20 introductory statistics students. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 57, 66, 69, 71, 72, 73, 74, 77, 78, 78, 79, 79, 81, 81, 82, 83, 83, 88, 89, 94 (a) the mean score is 77.7 points. with a standard deviation of 8.44 points. use this information to determine if the scores approximately follow the 68-95-99.7% rule. (b) do these data appear to follow a normal distribution? explain your reasoning using the graphs provided below.

What adds to be the bottom number but also multiplies to be the top number with 8 on the bottom and 15 on top