Kaprekar's sequence - maths

We loved our Math challenge today and we were excelelnt at explaining what happened! We used calculators to investigate Kaprekar's sequence: Choose a two digit number 96 Reverse the number 69 Take away the smallest two digit number from the largest two digit number 96 - 69 = 27 Add the two digits you are left with 2+7 = 9 We had to discuss What do you notice? What has happened? Was this the case for every number?  Try it at home and see what happens!