Q7 of 108 Page 32

If a variable X takes values 0, 1, 2, ….., n with frequencies nC0, nC1, nC2, …….nCn, then write variance X.

we know, mean x =




Hence,


More from this chapter

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5

In a series of 20 observations, 10 observations are each equal t k, and each of the remaining halves is equal to –k. If the standard deviation of the observation is 2, then write the value of k.

 6

If each observation of a raw data whose standard deviation is σ is multiplied by a, then write the S.D. of the new set of observations.

 1

For a frequency distribution mean deviation from mean is computed by

 2

For a frequency distribution standard deviation is computed by applying the formula