Page 28 - PlayFacto_K10
P. 28
Counting on 1 or 2, counting back 1 or 2
Use a number line to count on to add. 10
+2
+1
0123456789
Start on 5 and move to the right 1 space is 6.
Start on 5 and move to the right 2 spaces is 7.
Use a number line to count back to subtract. 10
-2
-1
0123456789
Start on 5 and move to the left 1 space is 4.
Start on 5 and move to the left 2 spaces is 3.
Example 1 Mark the number where the rabbit will stop.
⑴ Start on 8 and move to the left 1 space.
0 1 2 3 4 5 6 7 8 9 10
⑵ Start on 2 and move to the right 2 spaces.
0 1 2 3 4 5 6 7 8 9 10
3. Jumping numbers 25
Use a number line to count on to add. 10
+2
+1
0123456789
Start on 5 and move to the right 1 space is 6.
Start on 5 and move to the right 2 spaces is 7.
Use a number line to count back to subtract. 10
-2
-1
0123456789
Start on 5 and move to the left 1 space is 4.
Start on 5 and move to the left 2 spaces is 3.
Example 1 Mark the number where the rabbit will stop.
⑴ Start on 8 and move to the left 1 space.
0 1 2 3 4 5 6 7 8 9 10
⑵ Start on 2 and move to the right 2 spaces.
0 1 2 3 4 5 6 7 8 9 10
3. Jumping numbers 25
