In this series, you are going to learn the tips and tricks to solve math problems related to squares in IBPS PO, IBPS Clerk, SBI PO, SBI Clerk, SSC CGL, SSC CHSL and other competitive exams. Not only are we going to discuss the basic concepts of how to find square, but we would also show you the smart methods to do some speed math.
We all understand that apart from accuracy, speed also plays an important role in all competitive exams, especially the IBPS PO, IBPS Clerk, SBI PO, SBI Clerk, SSC CGL, SSC CHSL. In a subject like Quantitative Aptitude, in order to solve the maximum number of questions in the given time limit, you should be able to calculate fast. Here, we would go through some techniques and shortcuts to finding squares of numbers that will help you cut down on the time spent on each question when appearing for IBPS PO, IBPS Clerk, SBI PO, SBI Clerk, SSC CGL, SSC CHSL and other competitive exams.
What Is Square Of x?
How to find square is an important concept that frequently is seen in all bank exams.
Square of x is nothing but the number x multiplied with itself.
Formula For How To Find Square Of A Number
Things To Remember To Find Square Of A Number
It is very important that we find the square of the given number with minimum time spent. If you want to perfect finding squares of a given number, you must first learn squares of numbers from 1 to 30.
An interesting thing to notice is how the units place for the square changes as the units place for the number changes. This would be helpful in finding out square roots.
- When a number ends with 1, the square root either ends with 1 or 9.
Square root of 81 is 9
Square root of 441 is 21
- When a number ends with 4, the square root either ends with 2 or 8.
Square root of 64 is 8
Square root of 324 is 18
- When a number ends with 9, the square root either ends with 3 or 7.
Square root of 289 is 17
Square root of 169 is 13
- When a number ends with 6, the square root either ends with 4 or 6.
Square root of 196 is 14
Square root of 676 is 26
- When a number ends with 25, the square root ends with 5.
Square root of 225 is 15
Square root of 625 is 25
- When a number ends with 00, the square root ends with 0.Square root of 400 is 20
Square root of 900 is 30
How To Find Squares Of Numbers More Than 30
Example 1: Find 632
Example 2: Find 722
Example 3: Find 422
Here is how finding square of a number in the Smart Method saves time:
1. The first number (a2) is always 2500, which is always fixed.
2. The second term (2ab) is b*100
3. The third term is b2
Example 1: Find 842
Example 2: Find 922
For numbers from 130 onwards, the base is taken as 150, 200, 250 and likewise. If you have a fair understanding of what to take as the base, it gets easier to find squares of bigger numbers.
And we also that the square of a number ending with 5 is always 25. Therefore, we need to only find digits in the first part of the square.
If you observe the initial digits of the square, it is always the product of the initial digit before 5 in the number itself multiplied by its next integer, as highlighted below.
752 = (7*8)25 = 5625
1952 = (19*20)25 = 38025
And so on.
This is nothing but the multiplication of complementary numbers.
Read our next post to understand how to find the square root of a perfect square. Ensure to use these smart methods when preparing for competitive exams like IBPS PO, IBPS Clerk, SBI PO, SBI Clerk, SSC CGL, SSC CHSL in 2018. And of course, Keep Practicing!