ben has finished homewok during holiday.he does 2/3 of remaining question each days. after 4 days, 4 question are left .how many question he all together to do ?

I assume you mean he has unfinished homework.

Each day he has 3 times as many questions as on the next day. So,

after 4 days he had 4 questions left
after 3 days he had 12 questions
after 2 days he had 36 questions
after 1 day he had 108 questions
He started with 324 questions.