SOLUTION: How would I solve the following problem? Mary is five years older than Sue. Twenty years ago, Sue was half as old as Mary is now. How old is Mary now?

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Question 1099711: How would I solve the following problem? Mary is five years older than Sue. Twenty years ago, Sue was half as old as Mary is now. How old is Mary now?
Found 2 solutions by Fombitz, MathTherapy:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Convert the sentences to algebraic equations and then solve them.
.
.
M=S%2B5
.
.
Twenty years ago,
S-20=%281%2F2%29%28M-20%29
2S-40=M-20
M-2S=-20
Substitute from above,
%28S%2B5%29-2S=-20
-S%2B5=-20
-S=-25
S=25
Now use either equation to solve for M.

Answer by MathTherapy(10551) About Me  (Show Source):
You can put this solution on YOUR website!
How would I solve the following problem? Mary is five years older than Sue. Twenty years ago, Sue was half as old as Mary is now. How old is Mary now?
You're seeking to find MARY'S age, so let MARY'S age be M

Then Sue's is: M - 5

We then get: matrix%281%2C3%2C+M+-+5+-+20%2C+%22=%22%2C+%281%2F2%29+%2A+M%29

matrix%281%2C3%2C+M+-+25%2C+%22=%22%2C+M%2F2%29

2M - 50 = M ------- Multiplying by LCD, 2

- 50 = M - 2M

Mary, or 

IGNORE anyone who says otherwise!