That one seemed self explanatory for both my boys - they both got stuck on the "standard subtraction algorithm" - I think this is what BlackCat is referring to in the post before mine. I was not able to figure it out to help Aiden, but when Nathan got there he figured it out with only 1 mistake and so passed the pre test meaning he didn't have to do heaps of examples.
I was so glad - cause it made no sense at all to me until Nathan pointed out you must leave the box empty if you are not changing the figure but for the total you must type the zero if that is the first of the 3 digit number.
