Lucia's back hurts! She figured out that the books in her backpack are 5 times heavier than the backpack itself. By what percent heavier is the backpack with the books inside, than the books by themselves?
If the books in the bag are 5 times heavier than the bag itself then the books and the backpack together are 6 times heavier than the backpack itself, so the backpack with the books is (6 ÷ 5) × 100% = 120% heavier than the book by themselves.
