could you post OA?
IMO C
We have two sets with the same number of terms:
A = {x1,x2,...,xn}
B = {y1,y2,...,yn}
sample standard deviation
We want to know if standard deviation of set A is greater than standard deviation of set B.
S(A) > S(B) ?
(1) R(A) > R(B)
The range R of a set of data is the difference between the highest and lowest terms in the set.
let us plug in numbers
for example B = {-50,-40,-30,-20,-10} and A = {-51,-31,-30,-29,-10}
R(A) = 41, R(B) = 40
S(A) < S(B)
second example B = {-50,-40,-30,-20,-10} and A = {-51,-31,-30,-29,-10}
R(A) = 41, R(B) = 40
S(A) > S(B)
INSUFFICIENT
(2) sets A and B are both evenly spaced sets
for example B = {-50,-40,-30,-20,-10} and A = {1,2,3,4,5}
S(A) < S(B)
second example B = {-50,-40,-30,-20,-10} and A = {100,200,300,400,500}
S(A) > S(B)
so it is INSUFFICIENT
but
statements 1 and 2 are together SUFFICIENT
example B = {-50,-40,-30,-20,-10} and A = {100,200,300,400,500}
R(A) > R(B)
S(A) > S(B)
hope it helps!
