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Question
A boy scored following marks in various class tests during a term; each test being marked out of 20.
15, 17, 16, 7, 10, 12, 14, 16, 19, 12 and 16
What are his mean marks?
Solution
Arranging the given data in ascending order:
7, 10, 12, 12, 14, 15, 16, 16, 16, 17, 19
Mean `(barx) = (x_1 + x_2 + x_3 + ....... + x_n)/n`
= `154/11`
= 14
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