Unit 3 – Addition and subtraction
Let’s add 32 to 55
Let’s add 30 to 55
2
1
+10
+1
+1
+10 +10
+10
+10 +10
55
55
65
75 85
86
87
65
75 85
+
=
+
+
+
=
=
Let’s add 32 to 155
3
+10
+10
+10 +2
155
165
175
185187
+
=
+
+
=
4 We can think about the place value of both numbers to help us add. Now let’s add 43 to 55.
55
+ 43
50 5
40 3
55 + 43 = 50 + 5 + 40 + 3 = 90 + 8 = 98
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03/05/2022 10:18
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