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Question
The mean of 18, 28, x, 32, 14 and 36 is 23. Find the value of x. Sum of data
Solution
∵ Mean = `"Sum of data"/"Number of data"`
`=> 23 = (18 + 28 + x + 32 + 14 + 36)/6`
`=> 23 = (128 + x)/6`
`=> 23 xx 6 = 128 + x`
⇒ 138 = 128 + x
⇒ 138 - 128 = x
∴ x = 10
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