400
Please tell if you are adding, subtracting, or multiplying in the word problem and then solve.
Three students wanted to buy a book that cost $21 at the book fair, but they did not have enough money. They decided to put all of their money together and then buy the book. Student#1 had $7, student#2 $6, and student #3 had $8. Do they have enough money to buy the book?
What is Addition ... Yes they have $21 and enough money to buy the book.