help

[ddm]

Is the product of a and b odd?

(1) a has only 2 factors

(2) b = 2x + 1, where x is an integer


OA-E

can some one please explain the answer cannot be C.

since it is already given that a has only 2 factors....it means that a is a prime factor which is a odd no.

and in statement 2 tells us that b must be odd.

[Suyog]

yaa... agree... B can be odd....

but a can be even or odd... 2 or 3

So ans can be even/odd

Choose(e)

[bha]

Is the product of a and b odd?

(1) a has only 2 factors

(2) b = 2x + 1, where x is an integer


OA-E

can some one please explain the answer cannot be C.

since it is already given that a has only 2 factors....it means that a is a prime factor which is a odd no.

and in statement 2 tells us that b must be odd.

for the product of a and b odd...both a and b have to odd..odd * odd is odd..
(1) a has only 2 factors
===> a is prime number..only prime numbers will have two factors 1 and number itself...hence a can be either even or odd...plus no details about b...hence insuff...

(2) b = 2x + 1, where x is an integer
===> b is odd...as 2x will alwyas be even..even + 1 will be odd...but no info about a..hence not suff
combining 1 and 2..
b is odd...a can be odd or even...hence no suff..
hence answer is E