Mastering Mental Mathematics

Mathematics is easy for some people, intriguing for some others and plain terrifying for the rest. Some of us even falter while doing the most basic of calculations. Say, for example, you walk into a shopping mall which is offering a big discount. You come across a dress which you really like and the price tag says Rs. 2999 and the board above says 35% discount. Do you find it difficult to calculate what the final price of that dress will be? If you do, you are not the only one.

This is where being an expert in mental mathematics can help in real life. The best part about it is that it is not even that difficult to master. You just need to remember a few easy tricks and solving these equations will be a piece of cake. Additionally, it will help you a lot and save precious time in your examinations. Certain tests, such as CAT, require the examinees to be real quick and being able to solve calculations in your head can help you go a mile in that direction.

There are hundreds of tricks that can be used to simplify mathematical equations. In this article, we will look at some of the basic and most useful ones.Break it up

Even the longest of equations can be broken up into smaller bits and solved relatively easily. Same with numbers. All that is required is a small amount of addition or subtraction.

For example, let’s look that that dress that you liked in the shopping mall with the 35% discount. Here, we need to calculate 35% of 3000 (for the sake of simplicity, let us assume that you are paying an extra rupee). What we can do to make this equation simpler is consider 35% as 3×10%+ 5%. We know that 10% of 3000 is 300 and 5% of 3000 will be half of that, i.e, 150. So, 35% of 3000 will be 3×300+150= 900+150=1050. Therefore, you get a discount of Rs.1050 on that dress you liked.

Simpler, isn’t it?

Think in terms of nearest the round number

Round numbers, usually those ending with 0s, are easier to handle. Converting your number into a convenient round number can help solve an equation mush faster.

Say, you need to subtract 583 from 6749. Looks messy, right? Now, convert 583 to 600 and remember the balance, that is, 17. It’s much easier to subtract 600 from 6749. The answer is 6149. All you need to do to get the correct answer now is add 17 to it and it becomes 6166. What started as a messy subtraction becomes a very simple addition.

Distribute and multiply

Multiplication is harder than addition or subtraction. However, there are ways in which those can be made simpler too. The distributive property of multiplication allows the numbers to be broken up and multiplied to get the same results.

For example, if you need to multiply 142 with 6, instead of doing it traditionally, what you can do is break 142 into 100+40+2 and multiply each by 6. So it becomes, 600+240+12 which is 852. You will not require a calculator to do multiplications in this way.

Mental mathematics is something you need to cultivate in your mind continuously. It is not something that you can mug up and apply in examinations. More than examinations, it helps in your daily life. Of course, it will take time and some effort from your side. But once you are able to master it, your life will be that much easier. Also, if you are preparing for competitive exams like CAT, it may well prove to be the decisive factor behind success or failure.

Here, we saw only the tip of the iceberg, namely, mental maths. For more insight into this topic or any other maths or related topics, download the Byju’s learning app.