 Subtraction of 3-digit numbers | Grade 3 | Learning Concepts Operations

Subtraction

• Subtraction is an operation used to calculate the difference between two numbers.
• The symbol used to denote subtraction is ‘−‘.
• Subtraction is the process of taking away one number or amount from another.
• The number from which another number is subtracted is called the minuend and the number which is subtracted is called the subtrahend.
• The result is called the difference.
• The subtrahend is always smaller than the minuend. Examples:

1. 352 - 153
2. 756 - 545

1. We can subtract 153 from 352 as: So, 100 + 100 - 1 = 200 - 1 = 199

Hence, 352 - 153 = 199

2. We can subtract 545 from 756 as: So, 100 + 100 + 10 + 1 = 211

Hence, 756 - 545 = 211

Subtraction of 3-digit numbers without borrowing

• Start subtracting digits from the ones place.
• Subtract the digits at the tens place
• Subtract the digits at the hundreds place

Let us discuss the subtraction of the three-digit number without borrowing by examples.

Examples:

1. 353 - 151
2. 756 - 545

1. 353-151 = Hence, 353 - 151 = 202

2. 756 - 545 = Hence, 756 - 545 = 211

Subtraction of 3-digit numbers with borrowing

• Start subtracting digits from the ones place. If the minuend is lesser than the subtrahend then subtraction is not possible. We need to borrow ten from the minuend at tens place and add with the minuend at ones’ place and then do the subtraction.
• Subtract digits at tens place. If the minuend is lesser than the subtrahend then subtraction is not possible. need to borrow ten from the minuend at hundreds place and add with the minuend at ones’ place and then do the subtraction.
• Repeat the process

Let us discuss the subtraction of the three-digit number with borrowing by example.

Examples:

1. 353 - 154
2. 756 - 548

1. 353 - 154 Hence, 353 - 154 = 199

2. 756 - 548 Hence, 756 - 548 = 208

The result of any subtraction can easily be checked using addition. To check whether the result of the subtraction (difference) is correct or not, one should add the subtrahend with the difference. If the sum results in the minuend, then the subtraction is correct.

Here, some examples are given below.

Examples:

Find the difference and check by addition:

1. 605 - 263
2. 689 - 354

1. 605 - 263 So, the difference is 342.

Now, to check the result is correct, add the difference with subtrahend and check if the sum is the minuend. Hence, it is clear that the answer of the subtraction is correct.

2. 689 - 354 So, the difference is 335.

Now, to check the result is correct, add the difference with subtrahend and check if the sum is the minuend. Hence, it is clear that the answer of the subtraction is correct.   • -