Consider the numbers 1,2,3,4,5,6,7,8,9,10. If 1 is added to each number, the variance of the numbers so obtained is (a) 6.5           (b) 2.87           (c) 3.87        (d) 8.25

Explanation

The given numbers are
`1,2,3,4,5,6,7,8,9,10`

After adding 1 we get

`2,34,5,6,7,8,9,10,11`

Now,

`∑x_i=2+3+4+5+6+7+8+9+10+11=65`

`∑(x_i)^2=4+9+16+25+36+49+64+81+100+121=505`

∴ Variance of the numbers so obtained.

`= (∑(x_i)^2)/(10)−((∑x_i)/(10))^2`

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