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Question
If the mean of 9, 8, 10, x, 14 is 11, find the value of x.
Solution
Given data is 9, 8, 10, x, 14.
Mean = 11
We know, Mean `(barX) = "Sum of observations"/"Total number of observations"`
⇒ 11 = `(9 + 8 + 10 + x + 14)/5`
⇒ 11 = `(41 + x)/5`
⇒ 41 + x = 11 × 5
⇒ 41 + x = 55
⇒ x = 55 – 41
⇒ x = 14
As a result, the value of x is 14.
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