SOLUTION: The sum of Alan's age and Bob's age is 40. The sum of Bob's age and Carl's age is 34. The sum of Alan's age and Carl's age is 42. How old is Bob?

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: The sum of Alan's age and Bob's age is 40. The sum of Bob's age and Carl's age is 34. The sum of Alan's age and Carl's age is 42. How old is Bob?      Log On


   

Question 868531: The sum of Alan's age and Bob's age is 40. The sum of Bob's age and Carl's age is 34. The sum of Alan's age and Carl's age is 42. How old is Bob?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1.A%2BB=40
2.B%2BC=34
3.A%2BC=42
Subtract eq. 1 from eq. 2,
A%2BC-A-B=42-40
4.C-B=2
Now add eq. 2 and eq. 4,
C-B%2BB%2BC=34%2B2
2C=36
C=18
Then,
18-B=2
B=16
and finally,
A%2B16=40
A=24