195697

We worked on this together and found it hard to explain. We looked at adding 10 to a number and realised that the ones digit does not change. so 6 becomes 16 and 3 becomes 13.

Our teacher suggested we wrote 6 as 06 because it has a 0 in the tens place. Then it was much easier to explain. 06 + 10 = 16 and 03 + 10 becomes 13.

then we could easily see that when you add 10 to a single-digit number you end up with a 1 in the 10s place so once you add the digits together it will be one more than the number you first thought of. So adding 9, will give you the number you first thought of.