Answer:
the number of book she can carry is 5 books
Step-by-step explanation:
backpack capacity = 18 lb
backpack can carry:
lunch = 1 lb
gym clothes = 2 lb
books = 3 lb per book
find:
how many books can she carry in her backpack?
backpack capacity = lunch + gym clothes + x books
let x be the number of books
18 = 1 + 2 + 3x
18 - 1 - 2 = 3x
15 = 3x
x = 15 / 3
x = 5
therefore, the number of book she can carry is 5 books