You can
put this solution on YOUR website! so after school the remaining work will be => 1- 1/3 = 2/3
He did 1/4 of the remining work before dinner
So remaing part will be 1-1/4 = 3/4
which equals to => 2/3 x 3/4 of whole the part
= 1/2
So he must do 1/2 of his home work after dinner.