Question 1064424
The sum of Mary's age and twice Ann's age is 43. Twice Mary's age is 11 more than Ann's age. How old are they? 
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M + 2A = 43
2M = A + 11
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Substitute for "A" and solve for "M"::
M + 2(2M-11) = 43
M + 4M - 22 = 43
5M = 65
Mary = 13 yrs
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A = 2M-11 = 26-11 = 15 yrs (Ann's age)
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Cheers,
Stan H.
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