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प्रश्न
If the mean of 8 , 14 , 20 , x and 12 is 13, find x.
उत्तर
Numbers are = 8, 14, 20, x, 12
Mean= 13
n = 5
`barx = (x_1 + x_2 + x_3 + .... + x_n)/n`
⇒ `13 = (8+ 14+20+x + 12 )/5`
⇒ `13 = (54+x )/5`
⇒ 54+X=65
⇒ x = 11
The value of x = 11
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