Posted by julia on .
how do you do the counting up method

counting up method 
mathtaculator,
this is used many times for subtraction.
lets take the example 198  46. 198 rounds up to 200, and 46 rounds up to 50. 200  50 = 150. However, that's not our answer. 198 = 2002. so the answer would be 2 added to 150. Also, 46 is 504. So the answer would be another +4 to 150. Thus 1502+4 = 152.