Question

To celebrate the first day of spring, Lin is putting stickers on some of the 100 lockers along one side of her middle school's hallway. She puts a skateboard sticker on every 4th locker (starting with locker 4), and a kite sticker on every 5th locker (starting with locker 5). Name three lockers that will get both stickers. After Lin makes her way down the hall, will the 30th locker have no stickers, 1 sticker, or 2 stickers? Explain how you know.

Answer 1

The 30th sticker will have a sticker. The sticker will be 1 sticker (Kite Sticker) which will be put on the locker by Lin. This is because, following the arithematic progression of the sticker placement:

Locker 5 = Kite sticker

locker 10 = Kite sticker

Locker 15 = Kite sticker

.

.

Locker 30 = Kite sticker

It could be seen that at locker 30, the sticker to be placed by Lin will be Kite sticker

Explanation: