June 2020
Beginner
256 pages
5h 38m
English
You’re given a frequent-buyer card for your local coffee shop. Each time you buy a cup of coffee you get a stamp on your card. When the card is filled, you get a free cup of coffee. Here are two different scenarios:
Card A: The card has 10 boxes for the stamps, and when you get the card, all the boxes are blank.
Card B: The card has 12 boxes for the stamps, and when you get the card the first two boxes are already stamped.
Question: How long will it take you to get the card filled up? ...