Question 990225
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M=Marie's age 21 years ago; A=Andy's age 21 years ago=3M 
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A+21=2(M+21)
3M+21=2M+42
M=21
ANSWER: Marie was 21 years old on her wedding day.
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CHECK:
A=3M=3(21)=63
A+21=2(M+21)
63+21=2(21+21)
84=2(42)
84=84