Question 1181825: Carmen is 12 years older than David. Five years ago, the sum of their ages was 28. How old is Carmen now?
Found 4 solutions by Darshil, greenestamps, josgarithmetic, MathTherapy:
Answer by Darshil(1)   (Show Source):
You can put this solution on YOUR website! Let assume that Carmen's age is x, & David's age is y.
Carmen is 12 years older than David Hence,
x = y + 12 ---- (1)
Five years ago, the sum of their ages was 28 so,
(x-5) + (y-5) = 28
x + y - 10 = 28
x + y = 38 ------ (2)
From Equation 1 & 2,
2x = 50
x = 25 year
So, Age of Carmen is 25 Year.
Answer by greenestamps(13209)  (Show Source):
You can put this solution on YOUR website!
Especially when you are first learning algebra, look for different ways of setting problems up. There are dozens of ways to set up this problem for solving using formal algebra; different ways of setting the problem up can make big differences in the amount of work required to find the answer.
The solution from the other tutor is fine -- but it translates the given information directly into equations, which leads to a solution requiring much more work than necessary.
Here is how I would set this problem up.
Do some simple mental work with the given information to make it easier to use:
"Five years ago, the sum of their ages was 28."
So now the sum of their ages is 28+10=38.
Since Carmen is 12 years older than David, let their ages be x+12 and x. Then
(x+12)+x=38
2x+12=38
2x=26
x=13
ANSWER: Carmen's age is x+12=25
Answer by josgarithmetic(39630)  (Show Source):
Answer by MathTherapy(10556)  (Show Source):
You can put this solution on YOUR website!
Carmen is 12 years older than David. Five years ago, the sum of their ages was 28. How old is Carmen now?
Let Carmen's age be C
Then David's is: C - 12
Since their ages summed to 28, 5 years ago, we get: C + C - 12 - 2(5) = 28
2C - 12 - 10 = 28
2C - 22 = 28
2C = 50
Carmen's age, or 
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