SAT ? of the Day new format

Read the following SAT test question, then click on a button to select your answer. Correct answer below

Add 8x to 2x and then subtract 5 from the sum. If x is a positive integer, the result must be an integer multiple of

1. 2


2. 5


3. 8


4. 10


5. 15

Explanation:
The mathematical expression given in the question is 8x + 2x – 5, which is equivalent to 10x – 5. The expression 10x – 5 can be factored as 5(2x – 1). For every positive integer x, 5(2x – 1) must be a multiple of 5. If x = 1, then 5(2x – 1) = 5, which is not an integer multiple of 2, 8, 10, or 15. Therefore, the correct answer is 5.

Difficulty: Medium
Question Type: Standard Multiple Choice
(Mathematics)