41 campers went rowing and 4 campers went hiking in the morning. 26 campers went rowing in the afternoon. How many campers went rowing and hiking in all?
: 
How many campers went rowing in the morning? 41
How many campers went hiking in the morning? 4
How many campers went rowing in the afternoon? 26
How many campers went hiking in the afternoon? 0
How many campers went rowing in all? 41 + 26 = 67
How many campers went hiking in all? 4
How many campers went rowing and hiking in all? 4