Set M contains seven integers and set N contains three values chosen

Lets take a random set here,

Let M be {1,2,3,4,5,6,7}
Here median = 4
mean = 4
range = 6 (7 - 1)

Considering statement 1,


As per statement, lets suppose N is a set of {1,4,7}
Then S.D of N is higher than S.D of M

But if N is a set of {3,4,5}
S.D. of N is equal to S.D. of N

Hence statement 1 itself is Insufficient.

Considering statement 2,


As per statement, N has the same range as M,
So two digits out of three are already fixed, that is, 1 and 7.
Hence, lets suppose N is a set of {1,4,7} or {1,6,7} or {1,3,7}
Then S.D of N is always higher than S.D of M which is more equally distibuted as compared to N.

Hence statement 2 itself is Sufficient.

That makes the answer as B

But another set that we can take here specifically is

Let M be {2,2,2,2,2,2,2} as in the stem it is mentioned



Now integers may be same or different, that is not mentioned.

If we take M as {2,2,2,2,2,2,2}, then

Considering statement 1,


Then N is {2,2,2}
Then S.D of N is equal to S.D of M

Hence statement 1 itself is Insufficient.[/color]
As we consider both the sets

Considering statement 2,


Then N is {2,2,2}
Then S.D of N is equal to S.D of M

Hence statement 2 itself is Insufficient.
As we consider both the sets

Considering Statement 1 and Statement 2 together, still no definite solution.

That makes the answer as E

Bunuel - Please suggest. Is my reasoning correct for this

Hi Bunuel ,
If we consider
M as ( 1,1,1,1,1,1,1 )
And as per II,
N will be (1,1,1).
In this case S.D. of N is not greater than S.D. of M . So we get a NO.

I feel the OA should be E or the author should write that the elements of M are different or unique to each other.

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