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प्रश्न
If 69.5 is the mean of 72, 70, ‘x’, 62, 50, 71, 90, 64, 58 and 82, find the value of ‘x’.
उत्तर
No. of terms = 10
Mean = 69.5
Sum of the numbers = 69.5 × 10 = 695 ...(i)
But sum of numbers = 72 + 70 + x + 62 + 50 + 71 + 90 + 64 + 58 + 82 = 619 + x ...(ii)
From (i) and (ii)
619 + x = 695
`\implies` x = 695 – 619
`\implies` x = 76
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