AlgebraMediumAges from a ratio now and a difference later
Algebra practice question
Kai is twice as old as Lee. In 6 years, Kai will be 8 years older than Lee. How old is Kai now?
Answer: 16
k = 2l and (k + 6) = (l + 6) + 8 → k = l + 8. So 2l = l + 8 → l = 8 and k = 16.
Common wrong answers
- If you answered 4
- 4 comes from 2l = 8, halving the difference.
- If you answered 8
- 8 is Lee's age.
- If you answered 22
- 22 is Kai's age in 6 years.
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