Page 64 - Start Up Mathematics_1

Addition Using Carry Over Method

Look at the steps we follow to add two 3-digit Common Mistake!
numbers with carry over.
H T O
H T O 1 1
Step 1: Add the ones. 3 5 6
3 5 6
6 + 7 = 13 + 5 8 7
+ 5 8 7 8 3 3 ()

13 Remember to add the
carried over digits.

H T O
1 Step 2: 13 is a 2-digit number. Write 3 in the ones
3 5 6
place and carry over 1 to the tens place. Add

+ 5 8 7 the tens including the 1 carried over.

14 3 1 + 5 + 8 = 14

H T O
1 1 Step 3: 14 is again a 2-digit number. Write 4 in the
3 5 6
tens place and carry over 1 to the hundreds

+ 5 8 7 place. Add the hundreds including the 1
carried over.
9 4 3
1 + 3 + 5 = 9

We can add more than two numbers also by following the same steps.

Look at the given examples.

T O H T O
1. 1 2. 1 1
4 5 2 6 5

2 3 3 7 4

+ 1 8 + 1 2 6

8 6 7 6 5

Add the ones and carry over Add the ones and carry over the tens
the tens digit of the sum. digit of the sum. Then add the tens in
Then add the tens. the same way. Lastly, add the hundreds.

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