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If SD of 15 items is 6 and each item is decreased by 1, find the SD of the new set.
$\begin {array} {1 1} (A)\;10 & \quad (B)\;6 \\ (C)\;11 & \quad (D)\;15 \end {array}$
jeemain
math
cbse
class11
statistics
variance-and-standard-deviation
easy
q90
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asked
Jan 31, 2014
by
thanvigandhi_1
retagged
Sep 10, 2014
by
sharmaaparna1
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1 Answer
If each item of a data is increased or decreased by the same amount.
The SD of the data remains unchanged.
$ \therefore $ SD of new set is 15
Ans : (D)
answered
Jan 31, 2014
by
thanvigandhi_1
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