To calculate the mean of the numbers 56, 77, 68, 63, 69, 68, 80, 71, and 63, first sum them: 56 + 77 + 68 + 63 + 69 + 68 + 80 + 71 + 63 = 616. Then, divide the total by the number of values, which is 9. Thus, the mean is 616 ÷ 9 = 68.44.
-20
59.5
50, 51, 52, 54, 55, 56, 57, 58, 60, 62, 63, 64, 65, 66, 68, 69, 70
54 55 56 57 58 60 62 63 64 65 66 68 69
Add them up. 50, 51, 52, 54, 55, 56, 57, 58, 60, 62, 63, 64, 65, 66, 68, 69, 70
68
-20
60, 62, 63, 64, 65, 66, 68, 69, 70
59.5
50, 51, 52, 54, 55, 56, 57, 58, 60, 62, 63, 64, 65, 66, 68, 69, 70
54 55 56 57 58 60 62 63 64 65 66 68 69
These: 51, 52, 54, 55, 56, 57, 58, 60, 62, 63, 64, 65, 66, 68, 69.
Add them up. 50, 51, 52, 54, 55, 56, 57, 58, 60, 62, 63, 64, 65, 66, 68, 69, 70
45, 46, 48, 49, 50, 51, 52, 54, 55, 56, 57, 58, 60, 62, 63, 64, 65, 66, 68, 69, 70
50, 51, 52, 54, 55, 56, 57, 59, 60, 62, 63, 64, 65, 66, 68, 69, 70, 72, 74, 75, 76
57, 58, 60, 62, 63, 64, 65, 66, 68, 69
All are composite except 61 and 67. Composite numbers: 60, 62, 63, 64, 65, 66, 68, 69, 70