Each chocolate costs RM 1.
So with the RM 15, you buy 15 chocolates.
Chocolate count: 15 chocolates
For every 3 chocolates that you eat, you can return the 3 wrappers and get 1 chocolate for free.
Eat the 15 chocolates. Return 15 wrappers and get 5 chocolates for free.
Chocolate count: 15 chocolates (eaten) + 5 chocolates (uneaten) = 20 chocolates
Eat the free 5 chocolates. Return 3 wrappers and get 1 chocolate for free.
Chocolate count: 20 chocolates (eaten) + 1 chocolate (uneaten) = 21 chocolates
Wrapper count: 2 wrappers (in hand)
Eat the free 1 chocolate. Return the 3 wrappers (2 from the previous chocolates and 1 from the one you just ate) and get 1 more free chocolate.
Chocolate count: 21 chocolates (eaten) + 1 chocolate (uneaten) = 22 chocolates
Eat the last chocolate. Keep the last wrapper.
So how many chocolates and how many wrappers in the end?
22 chocolates. 1 wrapper.
Mystery solved ;-)
My momma always said, “Life is like a box of chocolates. You never know what you’re gonna get.” - Forrest Gump