SOLUTION: jenifer is 6 years older than sue. in 4 years she will be twice as old as sue was 5 years ago. find their ages now.

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Question 173722: jenifer is 6 years older than sue. in 4 years she will be twice as old as sue was 5 years ago. find their ages now.
Answer by solver91311(24713) About Me  (Show Source):
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Jennifer's age now: j

Sue's age now: s

Jennifer's age 4 years from now: j%2B4

Sue's age 5 years ago: s+-+5

Twice as old as Sue was 5 years ago 2%28s+-+5%29

Jennifer is 6 years older than Sue: j+=+s+%2B+6 (Equation 1)

In 4 years Jennifer will be twice as old as Sue was 5 years ago: j%2B4=2%28s-5%29 (Equation 2)

Substitute the expression for j from Equation 1 into Equation 2:

cartoon%28red%28j%29%2B4=2%28s-5%29%2Cred%28%28s%2B6%29%29%2B4=2%28s-5%29%29

Now solve for s

s%2B6%2B4=2%28s-5%29 → s%2B10=2s-10 → s-2s=-10-10 → -s=-20 → s=20

If Sue is 20 years old, Jennifer must be 20+%2B+6+=+26 years old.

4 years from now, Jennifer will be 30, 5 years ago, Sue was 15, and 30 is twice 15. Answer checks.