LCM for 20 and 45
What's the Least Common Multiple (LCM) of 20 and 45?
(One hundred eighty)
Finding LCM for 20 and 45 using GCF's of these numbers
The first method to find LCM for numbers 20 and 45 is to find Greatest Common Factor (GCF) of these numbers. Here's the formula:
LCM = (Number1 × Number2) ÷ GCF
GCF of numbers 20 and 45 is 5, so
LCM = (20 × 45) ÷ 5
LCM = 900 ÷ 5
LCM = 180
Finding LCM for 20 and 45 by Listing Multiples
The second method to find LCM for numbers 20 and 45 is to list out the common multiples for both nubmers and pick the first which matching:
Multiples of 20: 20, 40, 60, 80, 100, 120, 140, 160, 180, 200, 220
Multiples of 45: 45, 90, 135, 180, 225, 270
So the LCM for 20 and 45 is 180
Finding LCM for 20 and 45 by Prime Factorization
Another method to find LCM for numbers 20 and 45 is to list all Prime Factors for both numbers and multiply the highest exponent prime factors:
All Prime Factors of 20: 2, 2, 5 (exponent form: 22, 51)
All Prime Factors of 45: 3, 3, 5 (exponent form: 32, 51)
22 × 51 × 32 = 180
Related Calculations
See Also
- Greatest Common Factor - Find the Greatest Common Factor (GCF) of two numbers
<a href="https://calculat.io/en/number/least-common-multiple-lcm-of/20--45">What is the LCM of 20 and 45? - Calculatio</a>
LCM Table
About "Least Common Multiple" Calculator
Least Common Multiple (LCM) also known as the Lowest Common Multiple or Smallest Common Multiple of 2 numbers - it is the smallest positive integer that is divisible by both numbers