Question

The mean deviation of the numbers 3, 10, 10, 4, 7, 10 and 5 from the mean is:

• A. 2
• B. 2.5
• C. 2.57
• D. 3
• E. 3.75

Hint:

To calculate the mean deviation, first find the mean of the numbers, then calculate the absolute deviation from the mean and find the average.

Answer 1

The Correct Option is C

The mean of the numbers is calculated as: \[ {Mean} = \frac{3 + 10 + 10 + 4 + 7 + 10 + 5}{7} = \frac{49}{7} = 7 \] Now, calculate the deviations from the mean: \[ |3 - 7| = 4, \quad |10 - 7| = 3, \quad |10 - 7| = 3, \quad |4 - 7| = 3, \quad |7 - 7| = 0, \quad |10 - 7| = 3, \quad |5 - 7| = 2 \] The mean deviation is the average of these deviations: \[ {Mean deviation} = \frac{4 + 3 + 3 + 3 + 0 + 3 + 2}{7} = \frac{18}{7} \approx 2.57 \]