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Calculate the mean deviation of the first five prime numb...

Calculate the mean deviation of the first five prime numbers.

A.

2.72

B.

5.6

C.

5.25

D.

13.6

Correct answer is A

The first five prime numbers are 2, 3, 5, 7 and 11

M.D = \(\frac {\sum (x - x̄)}{n}\)

n = 5

\(x̄ = \frac {\sum x}{n} = \frac {2 + 3 + 5 + 7 + 11}{5} = \frac {28}{5} = 5.6\)

M.D = \(\frac {(2 - 5.6) + (3 - 5.6) + (5 - 5.6) + (7 - 5.6) + (11 - 5.6)}{5}\)

= \(\frac {(-3.6) + (-2.6) + (-0.6) + (1.4) + (5.4)}{5} = \frac {13.6}{5}\)

Take the absolute value of all numbers in bracket

= \(\frac {3.6 + 2.6 + 0.6 + 1.4 + 5.4}{5} = \frac {13.6}{5}\)

\(\therefore M.D = 2.72\)