52 campers went rowing in the morning. 61 campers went rowing in the afternoon. How many more campers went rowing in the afternoon than in the morning?
. 

There are 52 campers who went rowing in the morning. 61 campers went rowing in the afternoon. How many more campers went rowing in the afternoon than in the morning?

There are 61 - 52 = 9 more campers who went rowing in the afternoon than in the morning.