ajith wrote:gmatnmein2010 wrote:Is the product of a and b odd?
(1) a has exactly 2 factors.
(2) b = 2x + 1, where x is an integer.
1) Insufficient - It talks only about a
2) insufficient - it talks only about b
Combining
1) shows that a is a prime number (2,5...)
2) shows that b is an odd number
The product can be odd or even
Hence E
I agree.
This question could have been more challenging if it was written that 2 is not a factor of a.
In that case,when we consider both the statements together,the product would always be an odd number.
This is because all prime no.s except 2 are odd.
Also,from statement 2 we know that b is an odd integer.
Odd x Odd =Odd
Hence,it could have been C.
That could have been a good trap.
It takes time and effort to explain, so if my comment helped you please press Thanks button
Just because something is hard doesn't mean you shouldn't try,it means you should just try harder.
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