LCM for 30 and 84

What's the Least Common Multiple (LCM) of 30 and 84?

Answer: LCM of 30 and 84 is 420

(Four hundred twenty)

Finding LCM for 30 and 84 using GCF's of these numbers

The first method to find LCM for numbers 30 and 84 is to find Greatest Common Factor (GCF) of these numbers. Here's the formula:

LCM = (Number1 × Number2) ÷ GCF

GCF of numbers 30 and 84 is 6, so

LCM = (30 × 84) ÷ 6

LCM = 2520 ÷ 6

LCM = 420

Finding LCM for 30 and 84 by Listing Multiples

The second method to find LCM for numbers 30 and 84 is to list out the common multiples for both nubmers and pick the first which matching:

Multiples of 30: 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 360, 390, 420, 450, 480

Multiples of 84: 84, 168, 252, 336, 420, 504, 588

So the LCM for 30 and 84 is 420

Finding LCM for 30 and 84 by Prime Factorization

Another method to find LCM for numbers 30 and 84 is to list all Prime Factors for both numbers and multiply the highest exponent prime factors:

All Prime Factors of 30: 2, 3, 5 (exponent form: 21, 31, 51)

All Prime Factors of 84: 2, 2, 3, 7 (exponent form: 22, 31, 71)

22 × 31 × 51 × 71 = 420

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 30 and 84? (The answer is: 420). Select the first number (e.g. '30') and the second number (e.g. '84'). 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
1584420
1684
17841428
1884252
19841596
2084420
218484
2284924
23841932
2484
25842100
26841092
2784756
288484
29842436
3084
31842604
3284672
3384924
34841428
3584
3684
37843108
38841596
39841092
4084840
41843444
428484
43843612
4484924

FAQ

What's the Least Common Multiple (LCM) of 30 and 84?

LCM of 30 and 84 is 420