Question 990780
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M=mother's age; S=son's age
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M=4S Use this to substitute for M.
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M+6=3(S+6) Substitute for M from above.
4S+6=3S+18
S=12
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ANSWER: The son is 12 years old.
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CHECK:
M=4(S)=4(12)=48yrs
Mother is 48 years old.
M+6=3(S+6)
48+6=3(12+6)
54=3(18)
54=54