SOLUTION: A family had fifteen children, each of them born a year and a half apart. The oldest child's age is eight times that of their youngest sibling's. How old is the oldest sibling?

Question 724762: A family had fifteen children, each of them born a year and a half apart. The oldest child's age is eight times that of their youngest sibling's. How old is the oldest sibling?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
A family had fifteen children, each of them born a year and a half apart. The oldest child's age is eight times that of their youngest sibling's. How old is the oldest sibling?
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Let a(1) = x
Then a(15) = 8x
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You have an arithmetic sequence with d = 1.5
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a(15) = a(1)+14*d
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8x = x + 14*1.5
7x = 21
x = 3 (age of the youngest child)
8x = 24 (age of the oldest)
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Cheers,
Stan H.

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