Let's present age of Girish is x years

and present age of Ramesh is y years.

30.5 years ago,

7(x-30.5)+2=y-30.5................(i)

After 2.5 years,

(y+2.5)=2(x-0.5).....................(ii)

simplify (ii), we get

y=2x-3.5.................................(iii)

Now put value of Y from (iii) in to (i)

7(x-30.5)+2=(2x-3.5)-30.5

7x-213.5+2=2x-34

5x=177.5

x=35.5

present age of girish is 35 & 1/2 years

35.5+12.5=48 years

after 12.5 years girish age will be 48 years