Lizzy: Alex needs to be 54 inches tall to ride the newest roller coaster at the theme park. He is 48 inches tall this year. He hears a rumor that for every hour he hangs upside down, he can grow 1/12 of an inch. Normally he grows 1/3 of an inch per month. On average, how many hours does he need to hang upside down each month to be tall enough next year to ride the rollercoaster?.
Me: Hmmm, let me think. I think this is the detailed solution:
He is 6 inches too short this year because 54 - 48 = 6. He will naturally grow 4 inches taller because 12 x (1 / 3) = 4. He needs to grow 2 inches from hanging because 6 - 4 = 2. He needs to hang for 24 hours because 2 / (1 / 12) = 24. He needs to hang for 2 hours a month because 24 / 12 = 2. Final answer: 2.