Question

the mean and the standard deviation of a data which is comprised of a set of ten positive numbers are 8 and 2 respectively. If the sum of squares of nine among the ten numbers is 599, what is the tenth number​

Answer 1

We know that S.D(ax+b)=∣a∣.S.D(x)

Here, a=−1,b=1

∴ Required standard deviation =∣−1∣×2.87=2.87

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