AlgebraMediumAges: sum with a relation
Algebra practice question
Maya is 4 years younger than her brother. Twice her brother's age plus three times Maya's age is 48. How old is her brother?
Answer: 12
Let the brother be b: 2b + 3(b − 4) = 48, so 5b − 12 = 48, 5b = 60, b = 12.
Common wrong answers
- If you answered 8
- 8 is Maya's age.
- If you answered 7.2
- 7.2 comes from 5b + 12 = 48 (adding 12 instead of subtracting).
- If you answered 9.6
- 9.6 comes from 5b = 48, forgetting the −12.
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