Number Line
653 – 238 = 415
-5
415
1.
2.
3.
4.
5.
-30
420
-3
450
-200
453
653
Start the bigger number.
Count back by the hundreds in the smaller number.
Count back by the tens in the smaller number.
Count back by the ones in the smaller number.
The number you land on is your difference.
586 + 143 = 729
+100
586
1.
2.
3.
4.
5.
+10
686
+4
696
+29
700
Start the bigger number.
Count forward by the hundreds in the smaller number.
Count forward by the tens in the smaller number.
Count forward by the ones in the smaller number.
The number you land on is your sum.
729