Question 861559
Boron is ten years older than his sister. In three years, he will be twice as old as she is now. How old are they now?
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Equations:
B = s + 10
B+3 = 2(s+3)
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Substitute for "B" and solve for "s"::
s+10 + 3 = 2s+6
s + 13 = 2s+6
s = 7 (Sister's age)
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B = s + 10 = 17 (Boron's age now)
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Cheers,
Stan H.
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