SOLUTION: Jack is eight years older than his sister. In three years he will be twice as old as she is, how old are they now?

Question 818940: Jack is eight years older than his sister. In three years he will be twice as old as she is, how old are they now?
Answer by TimothyLamb(4379) (Show Source): You can put this solution on YOUR website!
j = s + 8
j + 3 = 2(s + 3)
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j + 3 = 2(s + 3)
s + 8 + 3 = 2s + 6
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s = 5
j = 13
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