AlgebraMediumTwo numbers from a sum and a relation
Algebra practice question
The sum of two numbers is 35, and the larger is 7 less than twice the smaller. What is the smaller number?
Answer: 14
Let the smaller be s: s + (2s − 7) = 35, so 3s = 42 and s = 14. (The larger is 21.)
Common wrong answers
- If you answered 21
- 21 is the larger number.
- If you answered 9.33
- 9.33 comes from 3s + 7 = 35 (adding 7 instead of subtracting).
- If you answered 17.5
- 17.5 halves 35, assuming the numbers are equal.
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