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• Addition within 20 by regrouping.
What will we learn today?
Whole Numbers
Mental Calculation
Here’s an example.
Here’s an example.
In the previous lecture, you have already learnt how to use the ‘count-on’ method.
Here’s an example.
In the previous lecture, you have already learnt how to use the ‘count-on’ method. Today, we will be learning how to add by making 10.
Here’s an example.
+
7 + 6 =
=
Here’s an example.
+ =
7 + 6 =
Here’s an example.
+
7 + 6 =
3
7 + 6 =
Split 6 into 3 and 3
Here’s an example.
+
7 + 6 =
3 3
7 + 6 =
Here’s an example.
+
7 + 6 =
3 3
7 + 6 =
7 and 3 make 10
Here’s an example.
+
7 + 6 = 10+3
3 3
7 + 6 =
7 and 3 make 10
Add 10 and 3
Here’s an example.
+
7 + 6 = 13
3 3
7 + 6 =
I think you’re really good!
Shall we try another question?
Here’s another example.
14 + 6 =
+
14 + 6 =
+
14 + 6 =
+
14
14 + 6 =
10 4 Regroup 14 into 10 and 4
+
14 + 6 =
14 + 6 =
10 4
Add the ones.4 and 6 make 10
+
14 + 6 = 10+10
14 + 6 =
10 4
Add the ones.4 and 6 make 10
+
14 + 6 = 20
14 + 6 =
10 4
Let’s try one more.
+ =
+ =
Do you know the answer?
+ =
Hint: Use regrouping method.
+ =
Add 8 and 2.
+ =
8 + 2 = 10
+ = 10+2
+ = 12
Are you ready to try out the questions?