• Adding two 2-digit numbers• Adding numbers using formal

algorithm • Solving 2-step word problems involving addition

What will we learn today?

Whole NumbersAddition Within 100

31 + 20 = _____

3 1

+ 2 0

5 1

Step 1 : Add the ones.

1 + 0 = 1

Step 2 : Add the tens.

3 + 2 = 5

Tens Ones

58 + 9 = _____

5 8

+ 9

6 7

Step 1 : Add the ones.

8 + 9 = 17You cannot have 2 digits on the same column, so you need to do renaming.

17 = 1 ten 7 0nesYou need to add the 1 ten to the tens place.

Step 2 : Add the tens.

5 + 1 = 6

Tens Ones

1

Word Problem

Mrs Tan baked 26 pies. Mrs Lee baked 5 more pies than Mrs Tan. How many pies did Mrs Tan and Mrs Lee bake in all?

26 + 5 = 31

31 + 26 = 57

They baked 57 pies in all.

2 6 + 5 3 1

1 3 1 + 2 6 5 7

Are you ready to try out the questions?