Subtraction of Bigger Numbers
In the previous lesson, we have learnt the subtraction of 1-digit and 2-digit numbers. Let's learn the subtraction of 3-digit numbers now.
Subtraction of 3-Digit Numbers
(i) Subtraction Without Regrouping
Find 726 - 314
Step 1: Arrange the numbers in columns.
726
- 314
Step 2: Subtract the ones. 6 - 4 = 2, write 2 in ones place.
726
- 314
2
Step 3: Subtract the tens. 2 - 1 = 1, write 1 in tens place.
726
- 314
12
Step 4: Subtract the hundreds. 7 - 3 = 4, write 4 in hundreds place.
726
- 314
412
726 - 314 = 412
726
- 314
Step 2: Subtract the ones. 6 - 4 = 2, write 2 in ones place.
726
- 314
2
Step 3: Subtract the tens. 2 - 1 = 1, write 1 in tens place.
726
- 314
12
Step 4: Subtract the hundreds. 7 - 3 = 4, write 4 in hundreds place.
726
- 314
412
726 - 314 = 412
(ii) Subtraction With Regrouping
In the previous example, the subtraction was easy as in each step, as the second digit in each step was smaller than the first digit in the same place.
Let's see another example.
Step 1: Arrange the numbers in columns.
5 7 2
- 2 8 4
Step 2: Subtract the ones. 2 - 4 is not possible, so we regroup 7 tens.
7 tens = 6 tens + 10 ones.
we add these 10 ones to 2 ones,
10 ones + 2 ones = 12 ones.
Now, subtraction is possible, 12 - 4 = 8, we write 8 in the ones place.
6 12
5 7 2
- 2 8 4
8
Step 3: Subtract the tens. 7 - 8 is not possible, so we regroup 5 hundreds.
5 hundreds = 4 hundreds + 10 tens.
we add these 10 tens to 7 tens,
10 tens + 6 tens = 16 tens.
Now, subtraction is possible, 16 - 8 = 6, we write 8 in the tens place.
4 16
5 7 2
- 2 8 4
8 8
Step 4: Subtract the hundreds. 4 - 2 = 2, we write 2 in the hundreds place.
5 7 2
- 2 8 4
2 8 8
5 7 2 - 2 8 4 = 2 8 8
5 7 2
- 2 8 4
Step 2: Subtract the ones. 2 - 4 is not possible, so we regroup 7 tens.
7 tens = 6 tens + 10 ones.
we add these 10 ones to 2 ones,
10 ones + 2 ones = 12 ones.
Now, subtraction is possible, 12 - 4 = 8, we write 8 in the ones place.
6 12
5 7 2
- 2 8 4
8
Step 3: Subtract the tens. 7 - 8 is not possible, so we regroup 5 hundreds.
5 hundreds = 4 hundreds + 10 tens.
we add these 10 tens to 7 tens,
10 tens + 6 tens = 16 tens.
Now, subtraction is possible, 16 - 8 = 6, we write 8 in the tens place.
4 16
5 7 2
- 2 8 4
8 8
Step 4: Subtract the hundreds. 4 - 2 = 2, we write 2 in the hundreds place.
5 7 2
- 2 8 4
2 8 8
5 7 2 - 2 8 4 = 2 8 8