LCM for 20 and 45

What's the Least Common Multiple (LCM) of 20 and 45?

Answer: LCM of 20 and 45 is 180

(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

See Also

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 45? (The answer is: 180). Select the first number (e.g. '20') and the second number (e.g. '45'). 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

LCM Table

Number 1Number 2LCM
54545
64590
745315
845360
945
1045
1145495
1245180
1345585
1445
1545
1645
1745765
1845
1945855
2045
2145
2245990
23451035
2445
2545
26451170
2745
28451260
29451305
3045
31451395
3245
3345495
34451530

FAQ

What's the Least Common Multiple (LCM) of 20 and 45?

LCM of 20 and 45 is 180