standard deviation of Q

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standard deviation of Q

by logitech » Tue Nov 25, 2008 11:21 pm
What is the standard deviation of Q, a set of consecutive integers?

(1) Q has 21 members.

(2) The median value of set Q is 20.

OA A
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by cramya » Wed Nov 26, 2008 1:28 am
Stmt I

Standard deviation is the same in cases where the number of elements stays the same but each element is increased by a constant.


SUFF
Stmt II

19 20 21

20 (set with 1 integer) i think its possible but we will see

STd dev different for the above set of numbers where the median is indeed 20. Dont know the number of elements

INSUFF

A)
Last edited by cramya on Wed Nov 26, 2008 5:43 am, edited 1 time in total.

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by rohangupta83 » Wed Nov 26, 2008 2:20 am
MGMAT question - exam set II

I got this question yesterday myself.

Cramya - so as long as we have the number of integers and the difference between them is constant (irrespective of the fact that they are consecutive). We should be able to find out the standard deviation.

for example:

we can find the standard deviation of a series of 10 integers where the first integer is 10 and the the difference between consecutive members of the series is 3.