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Question
The mean of the number 6, ‘y’, 7, ‘x’ and 14 is 8. Express ‘y’ in terms of ‘x’.
Solution
No. of terms = 5 and mean = 8
Sum of numbers = 5 × 8 = 40 ...(i)
But sum of numbers = 6 + y + 7 + x + 14 = 27 + y + x ...(ii)
From (i) and (ii)
27 + y + x = 40
x + y = 13
y = 13 – x
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