You are given a math word problem and you are supposed to only use subtraction on the numbers embedded in the text to answer the following question and then only report the final numerical answer.

Context: Paul had 42 pens and 143 books. After selling some books and pens in a garage sale he had 113 books and 19 pens left. 

 Question: How many pens did he sell in the garage sale?
23

Context: Paco had 6 cookies. He gave 30 cookies to his friend and ate 23 cookies. 

 Question: How many more cookies did he give to his friend than those he ate?
7

Context: Mary is baking a cake. The recipe calls for 9 cups of flour and 5 cups of sugar. She already put in 3 cups of flour and 62 cups of sugar. 

 Question: How many more cups of flour does she need to add?

6