Table Of Contents
Last updated on November 29th, 2024
LCM helps to solve problems with fractions and scenarios like scheduling or aligning repeating cycle of events. In this article, we will learn how to learn LCM by using different methods, learn to solve a few problems applying the LCM.
The LCM of 30 and 40 is the smallest positive integer, a multiple of both numbers. By finding the LCM, we can simplify the arithmetic operations with fractions to equate the denominators.
There are various methods to find the LCM, Listing method, prime factorization method and division method are explained below;
The LCM of 30 and 40 can be found using the following steps;
Step 1: Write down the multiples of each number:
Multiples of 30–30,60,90,120,150,…
Multiples of 40–40,80,120,…
Step 2: Ascertain the smallest multiple from the listed multiples of 30 and 40.
The LCM of 30 and 40 = 120
The prime factors of each number are written, and then the highest power of the prime factors is multiplied to get the LCM.
Step 1: Find the prime factors of the numbers:
Prime factorization of 30= 3×5×2
Prime factorization of 40 = 2×2×5×2
Step 2: Multiply the highest power of each factor ascertained to get the LCM:
LCM (30,40) = 120
The Division Method involves simultaneously dividing the numbers by their prime factors and multiplying the divisors to get the LCM.
Step 1: Write down the numbers in a row;
Step 2: A prime integer that is evenly divisible into at least one of the provided numbers should be used to divide the row of numbers. Continue dividing the numbers until the last row of the results is ‘1’ and bring down the numbers not divisible by the previously chosen prime number.
Step 3: The LCM of the numbers is the product of the prime numbers in the first column, i.e, LCM (30,40) = 120
Verify LCM(a,b)×HCF(a,b)=a×b, where a= 30 and b=40.
Find the LCM of 30 and 40 using the formula.
Find x where, LCM (30,x)=120 and HCF(30,x)=10.
Hiralee Lalitkumar Makwana has almost two years of teaching experience. She is a number ninja as she loves numbers. Her interest in numbers can be seen in the way she cracks math puzzles and hidden patterns.
: She loves to read number jokes and games.