Children often face difficulties and make errors while doing subtractions. In fact, even adults make calculation errors while performing the simplest subtractions. This is where Vedic Maths comes in as it offers the easiest tricks to calculate without any errors.
In this blog, we will uncover tricks for subtractions to help your child calculate faster, and that too, without any errors.
However, before we get started with the tricks, we have to understand two concepts. Your child can understand both these concepts within five minutes but they will list a lifetime:
Concept 1 (Match and Mismatch)
To perform subtractions through Vedic maths tricks, it is crucial for your child to understand that smaller numbers can be subtracted from greater numbers but greater numbers can’t be subtracted from smaller numbers. This is the concept of Match and Mismatch.
For example,
- 8–5 is possible. You will get the answer as 3
- However, 3–6 is not possible
In the first example, subtraction is possible because the minuend (8) is greater than the subtrahend (5) and so the numbers are matched. Whereas, in the second example, 6 can’t be subtracted by 3. So, the second set is mismatched.
In short, the numbers are matched if subtraction is possible and vice versa.
Concept 2 (Complements)
Complements are the unit digit numbers, which give the sum as 10.
For example,
- If we add 7 to 3, the answer will be 10.
- Similarly, if we add 3 to 7, the answer will again be 10. So, 7 and 3 are complements.
In this manner, 1 & 9 become complements because their sum is always 10. So, we have five sets of complements. They are:
- 2 & 8
- 3 & 7
- 4 & 6
- 5 & 5
There is no need to memorize these numbers because they will make their way to permanent memory with just a little bit of practice.
Now that the concepts are clear, let us move towards our Vedic maths subtraction trick.
Trick 1
Ask your kid to solve the following problem:
98
- 21
___
It would be easy for children to subtract the above numbers and write the solution as 77. It is because there is no need to carry out the numbers. However, your child might take more time to solve this problem:
92
- 47
___
Now, let us try to solve this problem by applying the Vedic Math sutras:
If you focus on the unit digit numbers, you can see that these are mismatched numbers because 7 (subtrahend) is greater than 2 (minuend). So, according to Vedic maths, when we deal with mismatched numbers, a dot is placed above the adjacent digit in the subtrahend (4) before we proceed with the calculations. We will get back to the dot later.
Now, it’s time to use the second concept which talks about complements. This concept is only required if the numbers are mismatched, like in the above example.
So, the complement for 7 (subtrahend) is 3. Now, by adding the complement number to the minuend (2) will give 5 like this:
92
.
- 47 (complement is 3)
___
5 (add 2+3)
Now, we placed a dot above 4. The dot symbolizes that we have to add 1 to the number. So:
4 + 1 = 5
It means, we have to subtract 5 from 9 to get:
92
.
- 47
___
45
Thus, we get 45 as the answer. It is simple as that!
The process is the same for any number, be it 3-digit, 6-digit, or 10-digit numbers. Let us subtract the following 4-digit problem using this trick:
7642
- 2835
______
By the same rule, we can put a dot over 3 in the tens place as the minuend at unit’s place (2) is smaller than subtrahend (5). Now, we add the complement of 5 (i.e. 5) to the minuend to get 7 (5 + 2). Then, the subtrahend at tens place becomes 4 and 4–4 = 0.
7642
.
- 2835
______
07
The next subtrahend (8) is, again, bigger than minuend (6), so we place a dot on the adjacent subtrahend (2), and add the complement of 8 to the minuend (6) to get 8 (6 + 2).
Lastly, 1 is added 2 and the sum (3) is subtracted from the minuend (7) to get:
7642
.
- 2835
______
4807
Trick 2
If you get a question like 10000–4568, simply subtract all the digits from 9 except for the last digit, which is to be subtracted by 10.
You will get 5432. Check it if you want!
We hope these tricks will help your children subtract faster. If your munchkin needs regular sessions of maths online classes, enroll your child in one of the sessions at PiggyRide.