Answer:
28 pieces.
Step-by-step explanation:
1/8 of 40 is 5. Subtract that five (the five that they ate) from 40, leaving you with 35. It says the next day, Ben ate 1/5 of what was left. He ate 1/5 of 35 which is 7. He ate 7 pieces. Subtract this from 35 and you're left with 28 pieces of calzone.