LCM for 20 and 90

What's the Least Common Multiple (LCM) of 20 and 90?

Answer: LCM of 20 and 90 is 180

(One hundred eighty)

Finding LCM for 20 and 90 using GCF's of these numbers

The first method to find LCM for numbers 20 and 90 is to find Greatest Common Factor (GCF) of these numbers. Here's the formula:

LCM = (Number1 × Number2) ÷ GCF

GCF of numbers 20 and 90 is 10, so

LCM = (20 × 90) ÷ 10

LCM = 1800 ÷ 10

LCM = 180

Finding LCM for 20 and 90 by Listing Multiples

The second method to find LCM for numbers 20 and 90 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 90: 90, 180, 270, 360

So the LCM for 20 and 90 is 180

Finding LCM for 20 and 90 by Prime Factorization

Another method to find LCM for numbers 20 and 90 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 90: 2, 3, 3, 5 (exponent form: 21, 32, 51)

22 × 51 × 32 = 180

LCM Table

Number 1Number 2LCM
590
690
790630
890360
99090
109090
1190990
1290180
13901170
1490630
1590
1690720
17901530
1890
19901710
2090
2190630
2290990
23902070
2490
2590450
26901170
2790270
2890
29902610
3090
31902790
32901440
3390990
34901530

About "Least Common Multiple" Calculator

This calculator will help you find the Least Common Multiple (LCM) of two numbers. For example, it can help you find out what's the Least Common Multiple (LCM) of 20 and 90? (The answer is: 180). Select the first number (e.g. '20') and the second number (e.g. '90'). After that hit the 'Calculate' button.
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

FAQ

What's the Least Common Multiple (LCM) of 20 and 90?

LCM of 20 and 90 is 180