SOLUTION: Kelly's sister is 5 years younger than double Kelly's age. If the sum of their ages is sixteen how old is Kelly's sister?

Question 694087: Kelly's sister is 5 years younger than double Kelly's age. If the sum of their ages is sixteen how old is Kelly's sister?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Kelly's sister is 5 years younger than double Kelly's age. If the sum of their ages is sixteen how old is Kelly's sister?
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Equations:
s = 2k-5
s + k = 16
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Substitute for "s" and solve for "k:
2k-5+k = 16
3k = 11
kelly = 11/3 3 yrs 8 months
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Solve for "s":
s = 2k-5
s = 22/3 - 15/3
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sister's age = 7/3 = 2yrs 4 months
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Cheers,
Stan H.
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