Question

Toni can carry up to 18 lb in her backpack. Her lunch weighs 1 lb, her gym clothes weigh 2 lb, and her books (b) weigh 3 lb each. How many books can she carry in her backpack?

Answer 1

The answer would be 5 books at 3lbs each is 15 and 1lb lunch and 2lb clothes.

Answer 2

Toni can carry up to 5 books

1+2+3b=18
combine 1 and 2
3+3b=18
subtract 3 from both sides
3b=15
divide 3 from both sides
b=5