How to calculate square of a number ending in 5

This technique will work for all numbers which end in 5.

Funda – If we remove the last digit ‘5’ from our number and are left with x, then the square will be [Product of x and x+1]25.

#Suppose we want to calculate 65^2.

ð  We remove 5 from our number, we are left with 6.

ð  Product of 6 and 7 is 42

ð  The square of 65 is 4225

#Suppose we want to calculate 195^2

ð  We remove 5 from our number, we are left with 19

ð  Product of 19 and 20 is 380

ð  The square of 195 is 38025

How to calculate square of a number ending in 1,9 or 4,6

This technique will work for all numbers which end at a distance of 1 unit from a multiple of 5.

Funda – Calculate the square of the nearest multiple of 5. Add or subtract (Num + Multiple of 5) from it.

#Suppose we want to calculate 61^2.

ð  The square of 60 is 3600

ð  The square of 61 will be 3600 + (60+61) = 3721

#Suppose we want to calculate 179^2

ð  The square of 180 is 32400

ð  The square of 179 is 32400 – (179+180) = 32041

#Suppose we want to calculate 66^2.

ð  The square of 65 is 4225

ð  The square of 66 will be 4225 + (65+66) = 4356

#Suppose we want to calculate 194^2

ð  The square of 195 is 38025

ð  The square of 194 is 38025 – (194+195) = 36736

I will continue with other methods of calculating squares in my next post.

You can buy my course on WizIQ here: Speed Calculations, Shortcuts & Tricks for CAT & Competitive Exams

Use the promo code BMSOFFER for an additional discount of 20%

The following two tabs change content below. #### ravihanda

Ravi Handa holds a B. Tech and M. Tech degree in Computer Science from one of the most prestigious Engineering colleges in India - IIT Kharagpur. In the last 7 years, he has trained and coached thousands of students via his website Handa Ka Funda. He also runs a comprehensive online CAT Coaching course #### Latest posts by ravihanda (see all)

BMS.co.in is aimed at revolutionising Bachelors in Management Studies education, also known as BMS for students appearing for BMS exams across all states of India. We provide free study material, 100s of tutorials with worked examples, past papers, tips, tricks for BMS exams, we are creating a digital learning library.

Disclaimer: We are not affiliated with any university or government body in anyway.

©2020 BMS - Bachelor of Management Studies Community 