Question 917140
Jack is four years younger than Mary. Mario is 6 less than twice the age of Mary. The sum of their ages is 22. What is Jack's age? 
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Equations:
j = m -4
r = 2m-6
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j + m + r = 22
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Substitute:
(m-4) + m + (2m-6) = 22
4m -10 = 22
4m = 32
m = 8 yrs
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jack = m-4 = 4 yrs (jack's age now)
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Cheers,
Stan H.
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