Question 205623
the difference between the ages of two sisters today is 3x. 6 years hence the ratio of their ages will be 7:6. what is the age of each sister today?
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Ages NOW:
a-b = 3x
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6yrs hence:
(a+6)/(b+6) = 7/6
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Substitute a = 3x+b from the 1st equation into the 2nd:
(3x+b-b)/(b+6) = 7/6
3x/(b+6) = 7/6
18x = 7b + 42
7b = 18x-42
b = (18x-42)/7 yrs (age of one of the sisters)
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Substitute that back into the 1st equation to solve for "a":
a -[(18x-42)/7] = 3x
a = 3x + [(18x-42)/7] (age of the other sister)
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Comment: That is a mess.  I have my doubts that is what
you are looking for.
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Cheers,
Stan H.