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A parent is three times as old as their child. If the parent is 31 years older than the child, what are their ages?

1 Answer

5 votes

Answer:

Child's age: 15.5

Parent's age: 46.5

Explanation:

Take child's age as C and parent's age as P

There are two conditions: P = 3C (parent is three times older than child), P = C + 31 (parent is 31 years older than child)

Therefore, 3C = C + 31

2C = 31

C = 31/2 = 15.5 (child's age)

P = 3C = 3 (15.5) = 46.5 (parent's age)

User Jonathon Reinhart
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