LCM and HCF Shortcut Tricks and Formulas
LCM and HCF Shortcut Tricks  Page 2
LCM and HCF Important Questions  Page 3
LCM and HCF Video Lecture  Page 4
Least Common Multiple (LCM) & Highest Common Factor(H.C.F)
Least Common Multiple (LCM) of two or more numbers is the smallest number that is a multiple of all the numbers.
Example: LCM of 3 and 4 = 12 because 12 is the smallest multiple which is common to 3 and 4 (In other words, 12 is the smallest number which is divisible by both 3 and 4)
LCM Example and Shortcuts
How to find out LCM using prime factorization method
We can find LCM using prime factorization method in the following steps
Step1 : Express each number as a product of prime factors.
Step2 : LCM = The product of highest powers of all prime factors
Example 1 : Find out LCM of 8 and 14
Step1 : Express each number as a product of prime factors. (Reference: Prime Factorization and how to find out Prime Factorization)
14 = 2 χ 7
Step2 : LCM = The product of highest powers of all prime factors
Here the prime factors are 2 and 7
The highest power of 2 here =
The highest power of 7 here = 7
Hence LCM = χ 7
Example 2 : Find out LCM of 18, 24, 9, 36 and 90
Step1 : Express each number as a product of prime factors (Reference: Prime Factorization and how to find out Prime Factorization).
18 = 2 χ
24 = χ 3
9 =
36 = χ
90 = 2 χ 5 χ
Step2 : LCM = The product of highest powers of all prime factors
Here the prime factors are 2, 3 and 5
The highest power of 2 here =
The highest power of 3 here =
The highest power of 5 here = 5
Hence LCM = χ χ 5 = 360
Hence Least common multiple (L.C.M) of 18, 24, 9, 36 and 90 = 2 × 2 × 3 × 3 × 2 × 5 = 360
How to find out LCM using Division Method (shortcut)
Step 1 : Write the given numbers in a horizontal line separated by commas.
Step 2 : Divide the given numbers by the smallest prime number which can exactly divide at least two of the given numbers.
Step 3 : Write the quotients and undivided numbers in a line below the first.
Step 4 : Repeat the process until we reach a stage where no prime factor is common to any two numbers in the row.
Step 5 : LCM = The product of all the divisors and the numbers in the last line.
Example 1 : Find out LCM of 8 and 14
Example 2 : Find out LCM of 18, 24, 9, 36 and 90
Hence Least common multiple (L.C.M) of 8 and 14 = 2 × 4 × 7 = 56
Latest Jobs

 Type
 Job Notification
 Job
 KVIC Recruitment of 108 GroupB and GroupC categories  Last Date 19012020
 Location
 MumbaiMaharashtra, India
 Date Posted
 7 Jan 2020

 Type
 Job Notification
 Job
 SAIL Durgapur Steel Plant Recruitment of Manager, Technician, Medical Service Provider  27012020
 Location
 DurgapurWest Bengal, India
 Date Posted
 7 Jan 2020

 Type
 Job Notification
 Job
 Indian Coast Guard Recruitment 260 Navik  Last Date 02022020
 Location
 Anywhere
 Date Posted
 7 Jan 2020

 Type
 Job Notification
 Job
 IOCL hiring 312 Apprentices  Last Date 22012020
 Location
 Anywhere
 Date Posted
 7 Jan 2020

 Type
 Job Notification
 Job
 RBI Recruitment NEWS for 926 Assistants  Last Date 16012020
 Location
 Anywhere
 Date Posted
 7 Jan 2020

 Type
 Job Notification
 Job
 Janki Devi Memorial College Recruitment 71 Assistant Professor  Last Date 04012020
 Location
 DelhiDelhi, India
 Date Posted
 2 Jan 2020

 Type
 Job Notification
 Job
 NPCIL Recruitment of Trainee, Electrician, Fitter, Machinist, Welder, Driver  Last Date 21012020
 Location
 RawatbhataRajasthan, India
 Date Posted
 2 Jan 2020

 Type
 Job Notification
 Job
 AIIMS Nagpur 104 Principal, Lecturer, Staff Nurse. Last Date 14012020
 Location
 NagpurMaharashtra, India
 Date Posted
 2 Jan 2020

 Type
 Job Notification
 Job
 Delhi Police Recruitment of 649 Head Constable  Last Date 27012020
 Location
 DelhiDelhi, India
 Date Posted
 2 Jan 2020

 Type
 Job Notification
 Job
 IBPS Recruitment Specialist Officers 1163 Vacancies  Last Date 26112019
 Location
 Anywhere
 Date Posted
 20 Nov 2019
Comment made by P.sujitha on Mar 6th 2019 at 5:11 am:
Find out LCM of 22,12
Comment made by Chandarvir Singh on Dec 1st 2019 at 7:19 am:
132
Comment made by shahab on Jul 11th 2019 at 3:37 am:
Help me hcf and lcm basic concept long tricks