Multiple choice

The mean deviation of first 8 composite numbers is

  1. $3.0$
  2. $4.83$
  3. $5.315$
  4. $3.5625$
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A Correct answer
Explanation

First 8 composite numbers: 4, 6, 8, 9, 10, 12, 14, 15. Mean = (4+6+8+9+10+12+14+15)/8 = 78/8 = 9.75. Mean deviation = sum|x - 9.75| / 8 = (|4-9.75| + |6-9.75| + |8-9.75| + |9-9.75| + |10-9.75| + |12-9.75| + |14-9.75| + |15-9.75|) / 8 = (5.75 + 3.75 + 1.75 + 0.75 + 0.25 + 2.25 + 4.25 + 5.25) / 8 = 24 / 8 = 3.0.

AI explanation

The first 8 composite numbers are 4, 6, 8, 9, 10, 12, 14, and 15. Their mean is calculated as the sum divided by 8: 78 / 8 = 9.75. The absolute deviations from the mean are 5.75, 3.75, 1.75, 0.75, 0.25, 2.25, 4.25, and 5.25. The sum of these absolute deviations is 24, so the mean deviation is 24 / 8 = 3. The mean deviation is 3.0.

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