Lois has 40 books. She gives a fourth of her books to her nephew. From her remaining books, she donates a third of her books to the library. Then she purchases 3 new books from the book store. How many books does Lois have now?
Lois gives 40 / 4 = <T>divide(40, 4)=10.0 books to her nephew
Then Lois has 40 - 10 = <T>subtract(40, 10)=30 books
Lois donates 30 / 3 = <T>divide(30, 3)=10.0 books to the library
Then Lois has 30 - 10 = <T>subtract(30, 10)=20 books
After purchasing new books, Lois has 20 + 3 = <T>add(20, 3)=23 books
