AlgebraMediumTwo numbers from a multiple and a difference
Algebra practice question
One number is 3 times another number, and the difference between the two numbers is 24. What is the smaller number?
Answer: 12
Let the smaller be x; the larger is 3x. Difference: 3x − x = 2x = 24, so x = 12. (The numbers are 12 and 36.)
Common wrong answers
- If you answered 6
- 6 is 24/4, treating the difference as 4x.
- If you answered 8
- 8 is 24/3, dividing the difference by 3. The difference is 3x − x = 2x, so divide by 2.
- If you answered 36
- 36 is the LARGER number. The question asks for the smaller.
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