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# The mean deviation for n observations x_{1}, x_{2}, ….., x_{n} from their mean is given by

A.

B.

C.

D.

Answer :

Let x_{1},x_{2},…x_{n} be n observation

And X is the aithemetic mean then,

We know, Standard deviation

So,

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The sum and the sum of squares of length x (in cm) and weight y (in g) of 50 plant products are given below:

Which is more variable, the length or weight?

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Which shows more variability, heights or weights?

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Who is more intelligent and who is more consistent?

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