Question 719656
David is 3 years older than his brother John. Three years ago John's age was 6 more than one-forth of david's age. what are their present ages ? 
-----
Equations:
d = j + 3
j+3 = (1/4)(d-3)+6
-------------------------
Rearrange:
d-3+3 = (1/4)(d-3)+6
---
4d = d-3 + 24
3d = 21
d = 7 yrs (David's age now)
----
j = d-3 = 4 yrs (John's age now)
-------------------
Cheers,
Stan H.
-------------------