Mathematics

Earlier today I set you this puzzle about PINs, the four-digit passcodes we use for phones and bank accounts. In the comments, many people said that the answer was obvious. These people fell into the trap. Perplexing PINs You and a friend are discussing how you choose four-digit PINs. You establish that neither of you … Read more

When it comes to choosing PIN numbers for our bank cards or our phones, the most popular numbers are the obvious ones , such as 1234, 1111, 1212 etc, according to what you read on the web. Today’s puzzle is about what is the best strategy when you choose the digits randomly. Perplexing PINs You … Read more