SOLUTION: I am now four times as old as my sister. When I am four times as old as I am now, my sister will still be less than thirty years old. How old is she now?

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Question 972566: I am now four times as old as my sister. When I am four times as old as I am now, my sister will still be less than thirty years old. How old is she now?

Found 2 solutions by josgarithmetic, MathTherapy:
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
b,s brother, sister;
x, more years;

b=4s, 4b=%28s%2Bx%29%3C30.

4%284s%29=s%2Bx%3C30
16s=s%2Bx%3C30
This looks like two simultaneous statements in variables s and x.
system%2816s=s%2Bx%2Cs%2Bx%3C30%29
system%2815s=x%2Cs%3C30-x%29
s%3C30-%2815s%29
s%3C30-15s
s%2B15s%3C30
16s%3C30
8s%3C15
s%3C15%2F8

Sister could be between 0 years and 1 year 10.5 months, exclusive.

Answer by MathTherapy(10553) About Me  (Show Source):
You can put this solution on YOUR website!

I am now four times as old as my sister. When I am four times as old as I am now, my sister will still be less than thirty years old. How old is she now?
Sister's age, or S+%3C+2%264%2F13, which suggests that sister can either be 1 year-old, or 2 years-old.