Steps:
1. since the least common multiple of 8 and 4 is 8, you would have to make both of the denominators 8.
2. 2 times 4 equals 8, 2 times 3 equals 6
3. 35 3/4 now becomes 35 6/8
4. your new problem is 35 6/8 - 1/8
5. 6 -1= 5
6. your answer is 35 5/8
did this answer your question...no. OK well that is your loss
So what you have to do to figure this out is 47-20 to get 27, then take 27 and divide it by 3 to get the answer of 9 comic books were sold by John.
The answer is B hope this helped