A. If the center plans to feed 700 people in 4 hours, then in order to find the average number of people the center is planning to feed each hour is 700/4 which is equal 175. So, the center is planning to feed 175 people per hour.
B. If during the first hour and a half, the center fed 270 people, find the remaining people to feed left: 700 - 270 = 430 people left to feed.