Question 115315: Ricardo is 4 years less than twice as old as his sister. The sum of their ages is 20. How old is Ricardo? Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! Ricardo is 4 years less than twice as old as his sister. The sum of their ages is 20. How old is Ricardo?
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EQUATIONS:
R = 2S-4
R+S = 20
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Solve by substitution:
2S-4+S = 20
3S = 24
S = 8 (Sister's age)
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Substitute to solve for R:
R = 2(8)-4
R = 12 (Ricardo's age)
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Cheers,
Stan H.
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