Question about MGMAT Guide 5 Number Strategies

[JoeD543]

Hello,

I hope this is in the correct location. I'm currently reviewing MGMAT Guide 5. On page 78 there is an example for testing Odds & Even cases in which a scenario table is presented.

I'm a bit confused on the portion that explains the answer eliminations, particularly answer choice 1 (a + c is odd). The explanation states that Scenario 1 goes against this statement. ODD + ODD = EVEN.

The problem that I'm seeing is Scenario 1 in the table is A: Odd and C: Even. Therefore A (Odd)+C(Even)=Odd.

Any help would be greatly appreciated. Thank you.


If a,b, and c are integers and ab+ c is odd, which of the following must be true?

I. a + c is odd
II. b + c is odd
III. abc is even

A) I only
B) II only
C) III only
D) I and III
E) II and III

Scenario a b c ab+c
1 O O E O
2 O E O O
3 E O O O
4 E E O O

[RonPurewal]

Hi,
Welcome to the forum. Unfortunately, this is the wrong folder for your question.

Please read the forum rules and familiarize yourself with the different folders on the forum. Then re-post this query in the correct folder (MGMAT non-CAT math).

Thanks.