Also with the trading off mental computation, 23 doesn't much the original problem of 67 - 36= 31. I think we have to add 4 to both the minuend and the subtrahend to get the same answer. Help
Hey there! In the power point where you're discussing the Trades-first algorithm, the final answer should be 25 right? Whenever you right in the subtrahend, the values should be the same correct? Because the original problem 52-27 is equal to 25 not 15. So we would keep the original subtrahend values right?
my biggest fan!! Saw you the other morning outside the firestation on the way to work. My son is always so excited to see the firetrucks in the morning!