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(1) a has only 2 factors => a is a prime number. It could be 2 (even) or 3 (odd). +No information about b. Insufficient (2) b = 2x + 1, where x is an integer => b=even+odd => b=odd. No information about a Insufficient

Together: b is odd, and a can be either odd or even (odd)(even)=even (odd)(odd)=odd Insufficient

Statement 1: not sufficient A could be 2 (even) or other prime # (odd). We would need to know if B is even or odd to answer the question.

Statement 2: not sufficient This tells us that B is odd since 2 times any number (even or odd) will be even. Add +1 to an even # and it will always be odd. We need to know if A is even or odd to answer the question.

Down to answer choices C and E.

When combined, we know that A is even or odd and that B is odd. If A is even, A*B would be even. If A is odd, A*B would be odd. Combined, the statements are not sufficient.

(1) a has only 2 factors (2) b = 2x + 1, where x is an integer

Kudos for a correct solution.

The product will be odd if both a and b are odd 1. a has two factors so a is prime...now if a=2,b=odd number then product is not even but if a=any other prime and b=odd number than product is odd...clearly we dont have enough information.. Option A and D ruled out

b=2x+1 so possible values for b=1,3,5,7...b= odd number...B ruled out

Combining both statements we can still have product even or odd..

ans E
_________________

“If you can't fly then run, if you can't run then walk, if you can't walk then crawl, but whatever you do you have to keep moving forward.”

From 1, we can say a can be 2, 3, 5, 7 ... any prime number. Donot know the value of b. Therefore, insufficient

From 2, we can say b is odd. But we don't know a. Therefore, insufficient.

Combining a) and b), we can't say whether the product of a and b is odd or even, since it depends on the value of "a" which can either be even (value = 2) or odd (primes other than 2).

Here we need to prove that A*B is odd Note => It is not specified whether they are integers or not. Statement 1 => A = prime => No clue of B A=2 B=3 => A*B=even A=3 B=5 => A*b= odd Not suff Statement 2 => B must be odd no clue of A not suff combining them we can say if A is 2 then AB is even else Ab will be odd since no boundary condition on A is given => not suff

(1) a has only 2 factors (2) b = 2x + 1, where x is an integer

Kudos for a correct solution.

FROM STATEMENT - IINSUFFICIENT

a can be both Odd / Even ; further we have no knowledge of b so, we can not find ab

FROM STATEMENT - IIINSUFFICIENT

If x = odd , 2x + 1 will be even If x = even , 2x + 1 will be odd

Since a consistent value of b can not be determined we can not find the value of ab... Thus, Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked, and additional data specific to the problem are needed, answer will be (E)

_________________

Thanks and Regards

Abhishek....

PLEASE FOLLOW THE RULES FOR POSTING IN QA AND VA FORUM AND USE SEARCH FUNCTION BEFORE POSTING NEW QUESTIONS

(1) a has only 2 factors (2) b = 2x + 1, where x is an integer

Kudos for a correct solution.

This question is just asking- is "a" an even number - simple even and odd properties

Statement 1

This just means "a" is prime; but 2 is an even prime number

Statement 2 This just mean B must be odd because any number multiplied by an even number is even and the sum of an even and odd number is odd. But even if this statement forces B to be odd, we still cannot say what A is.