A palindromic number is any number which has the same value when read from either direction.

Try this:

• Write down any 3 digit number.
• Under it write down the number you get by reversing the digits in your original number.
• Add the two numbers.
• If the number is a palindrome, stop. If the number is not a palindrome, under it write down the number you get by reversing its digits.
• Add these two numbers.
• Repeat this process until you get a palindrome.
• Count the number of times that you had to add in order to reach the palindrome. That number is the palindrome order of the number you started with.

Some examples:

        423             4782
      + 324           + 2874
      -----           ------
        747             7656
                      + 6567
                      ------
                       14223
                     + 32241
                     -------
                       46464

• See how many 3-digit numbers of palindrome order 1 you can find.
• See how many 4-digit numbers of palindrome order 1 you can find.
• What has to be true about any number with palindrome order 1?
• What is the largest three digit number with a palindrome order of 1?
• See how many numbers of palindrome order 3 you can find.
• What would it mean for a number to have a palindrome order of 0?
• Find a number with a palindrome order of 10 or more.

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