Question 335851
John is three times as old as Sarah. 
J = 3S
Last year John was four times as oid as Sarah. 
(J-1) = 4(S-1)
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So how old is Sarah and John now??
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Substitute for "J" and solve for "S":
(3S-1) = 4(S-1)
3S-1 = 4S-4
S = 3 yrs. old (Sarah's age now)
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Since J= 3S, J = 3*3 = 9 yrs old (John's age now)
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Cheers,
Stan H.
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