which of the following is NOT true?

[ektamatta]

If –2<a<11 and 3<b<12, then which of the following is NOT true?
(A) 1<a+b<23
(B) -14<a-b<8
(C) -7<b-a<14
(D) 1<b+a<23
(E) -24<ab<132

OA is C

[ksh]

Hi ektamatta,

I think we need to backsolve this problem

from which we can conclude that only c is not true

b-a would give a range from -8 to 14
so, -8<(b-a)<14
which is not in the answer option.