I'm stuck on a practice problem that seems so easy but I'm drawing a blank. I need to explain what the "student" was doing and why in steps 1&2. I need to figure out a computation to complete the problem using the method the "student" is using.
67+86
step 1: 7x2=14
14-1=13
step 2: 6+8=4+10= 14 so 60+80=140
67+86
step 1: 7x2=14
14-1=13
step 2: 6+8=4+10= 14 so 60+80=140