Question 269775: Mrs. Johnson is 3 times as old as her son. Ten years ago she was 5 times as old as her son was then. Find each of their ages. Answer by Stitch(470) (Show Source):
You can put this solution on YOUR website! Set Up:
-------------
Let Mrs. Johson's age = A
Let the son's age = B
Equation 1: (She is tree times as old as here son)
Equation 2: (She was 5 times as old 10 years ago)
Solution:
------------
We can substitute 3B into equation 2 for A
Equation 2: Simplify Subtract 3B from both sides Add 50 to both sides Simplify Divide both sides by 2
Now we can plug 20 into equation 1 for B
Equation 1:
Check you Answers
-----------------
Plug you values back into both equations to check them
Equation 1:
Equation 2:
(