• Adding two 2-digit numbers • Adding numbers using formal algorithm • Solving 2-step word problems involving addition What will we learn today? Whole Numbers Addition Within 100
Nov 29, 2014
• 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?