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Question
The mean deviation of the numbers 3, 4, 5, 6, 7 from the mean is
Options
25
5
1.2
0
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Solution
1.2
\[\text{ Mean } \left( X \right) = \frac{3 + 4 + 5 + 6 + 7}{5}\]
\[ = \frac{25}{5}\]
\[ = 5\]
Taking the absolute value of deviation of each term from the mean, we get:
\[MD = \frac{\left| (3 - 5) \right| + \left| (4 - 5) \right| + \left| (5 - 5) \right| + \left| (6 - 5) \right| + \left| (7 - 5) \right|}{5}\]
\[ = \frac{2 + 1 + 0 + 1 + 2}{5}\]
\[ = \frac{6}{5}\]
\[ = 1 . 2\]
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