SOLUTION: Frank is 6 years older than Mark. three years ago Frank was 4 times as old as Mark, How old is Mark?

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Question 603934: Frank is 6 years older than Mark. three years ago Frank was 4 times as old as Mark, How old is Mark?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Frank is 6 years older than Mark. three years ago Frank was 4 times as old as Mark, How old is Mark?
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Equations:
f = m + 6
(f-3) = 4(m-3)
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Substitute for "f" and solve for "m":
(m+6-3) = 4m-12
m+3 = 4m-12
3m = 15
mark = 5 yrs
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cheers,
Stan H.
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