Paco had 41 cookies. He ate some of them and had 23 cookies left. How many cookies did Paco eat?
1. Paco had 41 cookies. 
2. He ate some of them. 
3. He had 23 cookies left. 

We want to know how many cookies Paco ate. 

We can use the information we have to solve this problem. 

We know that Paco had 41 cookies to start with. 

We know that he had 23 cookies left. 

We want to know how many cookies he ate. 

We can solve this problem by subtracting. 

We can subtract the number of cookies he had left from the number of cookies he had to start with. 

41 - 23 = 18 

Paco ate 18 cookies.