Question

write the formula to find mean,varianceand standard deviation for a discrete data

Answer 1

HEY...
HERE IS UR ANSWER
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DIRECT METHOD =
sigma(fi * xi) / sigma fi
----------/-/-
ASSUMED MEAN METHOD =
A + {sigma(fi * di) / n }
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STEP DERIVATION METHOD
= A + { h * (sigma fi * ui) / sigma fi}

Answer 2

Mean:-x~=summution x
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n

Standard deviation :- S=√€(x-x~)2
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n

Descrete variable:- S2=€(x-x~)2 f
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n
Where:n=€f