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Regrouping Hundreds and Tens

Sometimes we need to regroup at more than one place while doing subtraction.

Let us understand this with the help of an example.

Example 3: Subtract 253 from 800.

Solution: Step 1. Write the smaller number below the bigger H T O
number in columns and start subtracting from the ones 8 0 0

place. – 2 5 3

Since there are no ones, regroup the tens and ones.

But there are no tens.
So, first regroup the hundreds and tens and then the tens and ones.

8 hundreds + 0 tens = 7 hundreds + 10 tens

and 10 tens + 0 ones = 9 tens + 10 ones

Step 2. Subtract the ones. Step 3. Subtract the Step 4. Subtract the

10 – 3 = 7 ones tens. hundreds.
H T O 9 – 5 = 4 tens 7 – 2 = 5 hundreds
9 H T O H T O

7 10 10 9 9
8 0 0 7 10 10 7 10 10
– 2 5 3 8 0 0 8 0 0

7 – 2 5 3 – 2 5 3
4 7 5 4 7

Thus, 800 – 253 = 547.

Shortcut Method In order to subtract numbers like 9, 99, etc.

from any number, we first subtract 10, 100,
When the last digits of the minuend etc. from the number, since that is easier.
are zeros, subtract 1 from both the Then, we add 1 to this difference to get the

numbers. It makes the subtraction answer. E.g. 46 – 9 = 46 – 10 + 1 = 37.

easier. Similarly, 465 – 99 = 465 – 100 + 1 = 366

H T O H T O As we have subtracted 100, which is 1

8 0 0 –1 7 9 9 more than 99, we add 1 to 365 to get the
– 2 5 3 –1 – 2 5 2 answer.
5 4 7 Now, find 730 – 9 and 730 – 99.

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