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Learning calculation tricks to solve math problems makes mathematics easier. In this article, we are going to explore some useful math tricks to solve complex mathematical problems quickly and correctly. These tricks help to generate answers mentally.
The majority of students that appear in competitive examinations fail to meet time restrictions. By learning and practicing calculation tricks one can meet time boundaries. Before solving math questions always read it carefully, develop its understanding, and if you are provided with some data try to develop a mathematical picture of it. Few useful tricks are listed below:
Addition
By these tricks, we can easily add large numbers mentally and can generate accurate answers even faster.
Making multiple of 10
Let’s add 244 and 567
First, make it round off to multiple of 10.
The number 244 would become 250
The number 567 would become 570
Then simple add these two rounded numbers (250 + 570). They result in 820.
Now calculate the extra numbers that we added to make them multiple of 10.
250–244=6
570–567=3
Now add 6 and 3, which is equal to 9 and then subtract this number from 820 which we got by adding multiples of 10.
820–9 = 811
So, the answer would be 811.
By adding tens and ones
Let’s suppose we want to add 23 and 56
First, separate tens and ones from both the numbers
20 and 3
50 and 6
First add tens
20 + 50 = 70
Then add ones
3 + 6 = 9
Now we will add tens and ones together
70 + 9 = 79
Answer is 79
By rounding to tens
Let’s suppose we want to add 79 and 62
First, we will check which number is near to multiple of ten.
In this situation, 79 is near to multiple of ten.
So we will make round of by adding 1
79 + 1= 80
Now we will subtract 1(which we added in 79 to make it 80) from 62
62–1 = 61.
Now we will simply add the numbers by breaking down in tens and ones
80 + 60 + 1 =141
Answer is 141
Subtraction
Few tricks are listed below for quick subtraction:
By rounding to tens
Lets’s take an example. We want to subtract 28 from 83
83–28 =?
First, look which number is nearest to multiple of 10. In this case 28 is near to 30. So we will make it 30 by adding 2, i.e.
28 + 2 = 30
Then, we will simple subtract 30 from 83
83–30 = 53
Now, we will add the number 2 which we added in 28 to make it 30
53 + 2 = 55
83–28 = 55
So, the answer would be 55
Splitting larger numbers into smaller numbers
In this method, we split larger numbers into smaller ones for quick solving
Lets suppose we want to subtract 912 from 1346
1346–912 =?
Lets split the numbers into hundreds and tens
1300–900 = 400
46–12 = 34
Now we will add both the answers
400 + 34 = 434
1346–912 = 434
In this way, answer would be 434
Sliding method
As we know subtraction is the difference between the two numbers. So if we slide them up by equal numbers that don’t make any change instead it would avoid borrowing.
Lets say we want to subtract 17 from 91
9 1
-1 7
In this situation we will slide them up by 3
91 would become 94
17 become 20. Now, we can easily subtract without borrowing
9 4
-2 0
7 4
Answer is 74
By choosing a middle number
Let's take an example. We want to subtract 2879 from 3121
First, we will select a middle number. In this example 3000 would be the middle point
Then we will calculate the difference between the two numbers from 3000
3000–2879 = 121
3121–3000 = 121
Now, we will add both the differences
121 + 121 = 242
Answer would be 242
By practicing we can master these simple mental math tricks and by using these math tricks we would be able to generate accurate answers and lesser time.
