One technique that can double your speed of calculations in Math
Swarnali Saha
Founder, Welcome2Maths | 15+ years as a Math Teacher & Life Skills Coach
Math is primarily about numbers and their relations. If you are not comfortable in number handling, data handling and data interpretation, you are not going to increase your confidence in Math. That is where Calculation in Math becomes so important. It’s the easiest way to build your Math Confidence.
Fast calculation skills can significantly boost your confidence and performance in math, allowing you to tackle problems with ease and enjoy the learning process. These skills are not only essential for academic success but also for real-life applications, from managing time and money to making quick decisions.
In this blog, I want to share with you one technique that can help you to do fast calculations in Math. This method is simple, practical, and designed to turn what might seem like a difficult task into an enjoyable and rewarding game. But before I tell you about the technique, let me share with you an important concept that you should understand to apply this technique.
Place Value Concept
The place value concept is fundamental to understanding and working with numbers in mathematics. If you understand it well it can transform your ability to do calculations in math. Place Value refers to the value of a digit depending on its position within a number. In our base-10 i.e. decimal number system, each place represents a power of 10. So the unit digit place is the zero power of 10, the tens place digit is the power one of 10, the hundreds place digit is the 2nd power of 10 and so on.
Let’s take an example. Consider the number 3,482. Each digit has a different value based on its position:
Let’s take an example. Consider the number 3,482. Each digit has a different value based on its position:
- The 2 is in one's place, representing 2.
- The 8 is in the tens place, representing 80.
- The 4 is in the hundreds place, representing 400.
- The 3 is in the thousands place, representing 3,000.
To find the total value of the number, we add these individual place values together: 3,000 + 400 + 80 + 2 = 3,482.
This concept forms the foundation for comparing numbers, performing mental calculations in math, and understanding the magnitude of numbers. For instance, recognizing that 450 is ten times larger than 45 is a direct application of place value knowledge. Then finding out which is greater between 2473 and 2791 in seconds can only be done through the application of the Place value concept.
Now I will share with you the technique that I referred to at the start of the blog- the method that can double your speed of calculations in math.
Breaking Down Numbers- A Simple yet Magical Technique
The basic idea behind breaking down numbers is to split a larger number into smaller components that are easier to work with. Normally the breaking down is done more on the basis of their place values to simplify the process of calculations in math.
Breaking down numbers is also known as number decomposition. It can serve as a powerful technique that simplifies complex calculations by dividing them into smaller, more manageable parts.
This method can be applied to addition, subtraction, multiplication, and division, making it an incredibly versatile tool for fast calculation in math. Let me give a step by step guide for each one of these operations.
Step-by-Step Guide
- Addition Example:
- Suppose you want to add 47 and 36.
- Break down the numbers according to their place value. 47 into 40 (tens place) and 7(unit place), and 36 into 30 (tens place) and 6 (unit place).
- First, add the tens: 40 + 30 = 70.
- Then, add the units: 7 + 6 = 13.
- Finally, combine the results: 70 + 13 = 83.
- Voila! Your addition is done. If you do this addition mentally, you will hardly take 5-10 seconds this way. Your speed of calculation in math, especially mental addition speed can improve significantly. You can also check this video lecture to learn how to use this concept for big additions.
- Subtraction Example:
Subtraction, as you know, can have 2 cases. One a simple subtraction and another subtraction with borrowing. In both cases, you can use this method of breaking down numbers to increase your speed of calculation in subtraction problems of math. Let’s check both the cases.
- First let’s check a simple case. Suppose you need to subtract 43 from 78.
- Break down the numbers according to their place value. 78 in to 70 (tens place) and 8 (unit place), and 43 in to 40 (tens place) and 3 (unit place).
- Now, subtract the tens: 70-40 = 30
- Then, subtract the units: 8-3 = 5
- Now add the two: 30+5 = 35. This is your answer.
- Now let’s check a case of borrowing. Suppose you need to subtract 58 from 94.
- Break down the numbers according to their place value. 94 into 90 (tens place) and 4 (unit place), and 58 into 50 (tens place) and 8 (unit place).
- First, subtract the tens: 90 - 50 = 40.
- Then, subtract the units: 4 - 8. Since this result is a negative number, adjust by borrowing from the tens place: (40 - 10) + (10 + 4 - 8) = 36. The result is 36.
- Multiplication Example:
- Let’s take the multiplication of 23 by 15, break down 23 into 20 (tens) and 3 (unit)
- So you can write: (20 + 3) x 15
- Multiply each part using distributive property and add the products: (20 x 15) + (3 x 15) = 300 + 45 = 345.
- So, you see, just by breaking one number, and applying the multiplication table of 15, we can answer the multiplication problem in seconds. So, this one technique can help us in increasing our speed of calculation in math in the area of multiplication too.
- Division Example:
- Now, for the last exam let’s take division 1440 by 12.
- Now in this case rather than breaking down on the basis of place value, let’s break on the basis of easy multiples. Example break 1440 into 1200 and 240.
- Divide each part by 12: 1200 ÷ 12 = 100 ; 240 ÷ 12 = 20
- Add the results: 100 + 20 = 120
- So, see how you can transform a division problem in a way that you can calculate fast considerably.
Conclusion:- Why this works & how to move ahead!
This technique works well because it reduces the cognitive load by simplifying the calculations of math. By handling smaller, simpler numbers, you can perform calculations more quickly and accurately.
By regularly practicing breaking down numbers, you can develop a solid foundation in fast calculation techniques, making math less intimidating and more enjoyable and ultimately resulting in the skill of super-fast calculation in math. This skill not only enhances your academic performance but also equips you with practical problem-solving abilities for everyday life. So, go ahead and use this technique and get things done fast. All the Best!