Question 236361
E =  Eddie's current age
M = Marco's current age

E/4 = M   (1)

After 10 years Eddie is twice Marco's age:



(E+10)/2 = M + 10  (2)


Make (1) = (2) by adding 10 to equation (1) :

E/4 + 10 = M + 10 = (E+10)/2

so

E/4 + 10 = (E+10)/2

Rearrange to get E on its own:

10 = (E+10)/2 - E/4

10 = (2E+20)/4 - E/4

10 = (E+20)/4

40-20 = E

So Eddie's original age was 20 and Marco's was 5. So their new age after 10 years is 30 and 15 respectively.

Is this clear?

Does it help?