Question 500712: Felipe is a teenager who is 10 years older than his sister Irene. In 6 years, Felipe will be twice as old as his sister. How old is Felipe?
Answer by oberobic(2304)   (Show Source):
You can put this solution on YOUR website! F = Felipe's age
I = Irene's age
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F = I +10
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In six years means:
F+6 = Felipe's age
I+6 = Irene's age
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(F+6) = (I+6)*2
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Substitute for F = I+10
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(I+10+6) = (I+6)*2
I + 16 = 2I +12
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Subtract I from both sides
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16 = I + 12
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Subtract 12 from both sides
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4 = I
so
Irene is 4
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Substitute to find F
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F = I +10
F = 4 + 10
F = 14
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Always check your work!
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In 6 years, F = 20.
In 6 years, I = 10.
He will be twice as old as she.
Correct!
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Answer:
Felipe is 14, and Irene is 4.
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Done.
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