SOLUTION: A woman is three times as old as her daughter. In four years time she will be two and a half times as old as her daughter. What is the woman's present age? m=3X d=x

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Question 845920: A woman is three times as old as her daughter. In four years time she will be two and a half times as old as her daughter. What is the woman's present age?
m=3X d=x
+4 yrs
m=3x+4*2.5 d=x+4
as far as I got with my daughter's maths question?? any ideas
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +m+ = mom's age now
Let d+ = Daughter's age now
+m+%2B+4+ = mom's age in 4 years
+d+%2B+4+ = daughter's age in 4 years
---------------------------------------------
(1) +m+=+3d+
(2) +m+%2B+4+=+2.5%2A%28+d+%2B+4+%29+
Substitute (1) into (2)
(2) +3d+%2B+4+=+2.5d+%2B+10+
(2) +.5d+=+10+-+4+
(2) +.5d+=+6+
(2) +d+=+12+
and
(1) +m+=+3d+
(1) +m+=+36+
Mom is 36
Daughter is 12
check:
(2) +m+%2B+4+=+2.5%2A%28+d+%2B+4+%29+
(2) +36+%2B+4+=+2.5%2A%28+12+%2B+4+%29+
(2) +40+=+2.5%2A16+
(2) +40+=+40+
OK