SOLUTION: A mother is 25 years older than her daughter. Five years ago, the daughter was half as old as the mother was then. How old is the daughter now?

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Question 232430: A mother is 25 years older than her daughter. Five years ago, the daughter was half as old as the mother was then. How old is the daughter now?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let m = Mother's age now
Let d = Daughter's age now
m+-+5 = Mother's age 5 years ago
d+-+5 = Daughter's age 5 years ago
given:
(1) m+=+d+%2B+25
(2) d+-+5+=+%281%2F2%29%2A%28m+-+5%29
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This is 2 equations and 2 unknowns, so it's solvable
Multiply both sides of (2) by 2
(2) 2%2A%28d+-+5%29+=+m+-+5
(2) 2d+-+10+=+m+-+5
(2) 2d+-+m+=+5
Subtract d from both sides of (1)
(1) -d+%2B+m+=+25
Add (1) and (2)
(2) 2d+-+m+=+5
(1) -d+%2B+m+=+25
d+=+30
The daughter is 30 years old
check answer:
(1) m+=+d+%2B+25
(1) m+=+d+%2B+25
m+=+55
(2) d+-+5+=+%281%2F2%29%2A%28m+-+5%29
(2) 30+-+5+=+%281%2F2%29%2A%28m+-+5%29
(2) 25+=+%281%2F2%29%2A%2855+-+5%29
25+=+%281%2F2%29%2A50
25+=+25
OK