Question 388994
Jeff is Three times as old as his son. 
In nine years, Jeff will be twice as old as his son. 
How old is each now?
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Equations:
j = 3s
(j+9) = 2(s+9)
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Substitute for "j":
(3s+9) = 2s+18
s = 9 (Son's age now}
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j = 3s = 27 (Jeff's age now)
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Cheers,
stan H.
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