Puzzle of the Day
Start with any two-digit number. Multiply each digit by itself then add these answers. Do the same thing to this new number and so on until something happens. For example 32 becomes 9+4 which is 13, 13 becomes 1+9 which is 10, 10 becomes 1+0 =1. This one ends at 1. What else happens when you start with different numbers?
Answer: All end with single digits, 2 is most frequent