There are so many people who detest math even at an older age but that is because of the wrong method of teaching which they would have attended in school. Math is a beautiful subject and the teachers in schools should help the students understand it’s beauty by its various features present. The art of learning the tricks and shortcuts to make math a skill rather than a burden will help the students to fall in love with this subject. Here in this article, we see few tricks for doing fast-math.  These tips will help students to do the calculation in their head and save a lot of time during exams as topics like Demorgan’s law would require the old school method of calculation.

Let’s look at few tricks and shortcuts which can help us do fast-math.

Subtracting a number from 1000

When a number is to be subtracted from 1000: The trick is to subtract every number with 9 except the final number in the sequence.  The final number should be subtracted by 10. This will help us do subtractions with 1000 a lot faster.

Let’s look at an example:

1000 – 432

  • Subtract 4 from 9 = 5
  • Subtract 3 from 9 = 6
  • Subtract 2 from 10 = 8

The answer is 568

Multiplying any number 5 times

When any number is said to be multiplied by 5, there are two quick easy methods to find its solution. We need to know whether the number multiplied with 5 is odd or even.

Let’s look an example for an instance of an even number.

5 x 8 =

  • First Step: Take the number to be multiplied by 5 and split it in half, this makes the number 8 which is given, to become 4
  • Second Step: Add a 0 to the number to find its answer. In this case, we see that the answer for the given example (5 x 8) is 40

5 x 7 =

  • First Step: Subtract 1 from the number which is to be multiplied by 5, in this instance the number 7, when subtracted will become the no. 6
  • Second Step: Divide the subtracted result into halves, i.e. the result which is 6 becomes the number 3. Make 5 the last digit.
  • Hence, we get the solution for the odd number i.e. 5 x 7 = 35

From these two easy tricks, we can calculate any number to be multiplied with 5.

Division Tricks:

Here are few tricks to know whether a number is divisible by certain numbers.

  • To check if the number is divisible by 10, the number should end with 0
  • To check if the number is divisible by 9, the digits should be added together and the total should be divided by 9.
  • To check if the number is divisible by 8, The last 3 digits should be divisible by 8 or should end with 000
  • To check if the number is divisible by 5, the number should end with 0 or 5.

As we have seen few out of the many tricks and shortcut techniques to help students in their exams and also make the students gain interest towards the subject. Even completed topics like Quadratic Equationor trigonometry can be made easy by various innovative methods. For more tips and tricks to learn concepts better, subscribe to our Byju’s YouTube Channel.