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प्रश्न
If the mean of x, x + 2, x + 4, x + 6 and x + 8 is 13, find the value of x. Sum of data.
उत्तर
∵ Mean = `"Sum of data"/"Number of data"`
`=> 13 = (x + (x + 2) + (x + 4) + (x + 6) + (x + 8))/5`
`=> 13 = (5x + 20)/5`
`=> 13 xx 5 = 5x + 20`
⇒ 65 - 20 = 5x
⇒ 45 = 5x
⇒ x = `45/5`
∴ x = 9
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