Question 1016949: twenty years ago, a mother was 4 times as old as her son 4 years hence,she will be twicw as old as her son .what are their present ages Answer by macston(5194) (Show Source):
You can put this solution on YOUR website! .
M=mother's age; S=son's age
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M-20=4(S-20)
M=4(S-20)+20
M=4S-80+20
M=4S-60
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M+4=2(S+4)
M=2(S+4)-4
M=2S+8-4
M=2S+4
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4S-60=2S+4
2S-60=4
2S=64
S=32
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M=4S-60=4(32)-60=128=60=68
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ANSWER: Son is 32 and mother is 68.
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CHECK:
M+4=2(S+4)
68+4=2(32+4)
72=2(36)
72=72
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