PSAT Math : How to add even numbers

Study concepts, example questions & explanations for PSAT Math

varsity tutors app store varsity tutors android store

Example Questions

Example Question #21 : Even / Odd Numbers

If x represents an even integer, which of the following expressions represents an odd integer?

Possible Answers:

3x + 1

5x + 4

x + 2

2x – 2

3x – 2

Correct answer:

3x + 1

Explanation:

Pick any even integer (2, 4, 6, etc.) to represent x. The only value that is odd is 3x + 1. Any number multiplied by an even integer will be even. When an even number is added and subtracted to that product, the result will be even as well. 3x + 1 is the only choice that adds an odd number to the product.

Learning Tools by Varsity Tutors