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प्रश्न
If x is the mean of the ten natural numbers `x_1, x_2 , x_3+....... + x_10` show that (x1 -x) + (x2 - x) +.........+ (x10 - x)` = 0
उत्तर
We have , x = `( x_1 + x_2 +...... + x_10) / 10`
⇒ `x_1 +x_2 + ..........+ x_10 = 10barx ..... (1)`
⇒ Now , `(x_1 - barx) + (x_2- barx)+.........+ (x_10 - barx)`
⇒ `10barx - 10barx` [By equation (1)]
∴ `(x_2- barx) + (x_2 - barx) +.......+ (x_10 - barx)`0 Hence proved.
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