What is the LCM of 21 and 30?

"Least Common Multiple" Calculator

What's the Least Common Multiple (LCM) of 21 and 30?

Answer: LCM of 21 and 30 is 210

(Two hundred ten)

Finding LCM for 21 and 30 using GCF's of these numbers

The first method to find LCM for numbers 21 and 30 is to find Greatest Common Factor (GCF) of these numbers. Here's the formula:

LCM = (Number1 × Number2) ÷ GCF

GCF of numbers 21 and 30 is 3, so

LCM = (21 × 30) ÷ 3

LCM = 630 ÷ 3

LCM = 210

Finding LCM for 21 and 30 by Listing Multiples

The second method to find LCM for numbers 21 and 30 is to list out the common multiples for both nubmers and pick the first which matching:

Multiples of 21: 21, 42, 63, 84, 105, 126, 147, 168, 189, 210, 231, 252

Multiples of 30: 30, 60, 90, 120, 150, 180, 210, 240, 270

So the LCM for 21 and 30 is 210

Finding LCM for 21 and 30 by Prime Factorization

Another method to find LCM for numbers 21 and 30 is to list all Prime Factors for both numbers and multiply the highest exponent prime factors:

All Prime Factors of 21: 3, 7 (exponent form: 3¹, 7¹)

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

3¹ × 7¹ × 2¹ × 5¹ = 210

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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 21 and 30? (The answer is: 210). Select the first number (e.g. '21') and the second number (e.g. '30'). 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

"Least Common Multiple" Calculator

LCM Table

Number 1	Number 2	LCM
6	30	30
7	30	210
8	30	120
9	30	90
10	30	30
11	30	330
12	30	60
13	30	390
14	30	210
15	30	30
16	30	240
17	30	510
18	30	90
19	30	570
20	30	60
21	30	210
22	30	330
23	30	690
24	30	120
25	30	150
26	30	390
27	30	270
28	30	420
29	30	870
30	30	30
31	30	930
32	30	480
33	30	330
34	30	510
35	30	210

LCM for 21 and 30

"Least Common Multiple" Calculator

What's the Least Common Multiple (LCM) of 21 and 30?

Finding LCM for 21 and 30 using GCF's of these numbers

Finding LCM for 21 and 30 by Listing Multiples

Finding LCM for 21 and 30 by Prime Factorization

Related Calculations

See Also

About "Least Common Multiple" Calculator

"Least Common Multiple" Calculator

LCM Table

FAQ

What's the Least Common Multiple (LCM) of 21 and 30?

See Also

Number 1	Number 2	LCM
6	30	30
7	30	210
8	30	120
9	30	90
10	30	30
11	30	330
12	30	60
13	30	390
14	30	210
15	30	30
16	30	240
17	30	510
18	30	90
19	30	570
20	30	60
21	30	210
22	30	330
23	30	690
24	30	120
25	30	150
26	30	390
27	30	270
28	30	420
29	30	870
30	30	30
31	30	930
32	30	480
33	30	330
34	30	510
35	30	210

Number 1	Number 2	LCM
6	30	30
7	30	210
8	30	120
9	30	90
10	30	30
11	30	330
12	30	60
13	30	390
14	30	210
15	30	30
16	30	240
17	30	510
18	30	90
19	30	570
20	30	60
21	30	210
22	30	330
23	30	690
24	30	120
25	30	150
26	30	390
27	30	270
28	30	420
29	30	870
30	30	30
31	30	930
32	30	480
33	30	330
34	30	510
35	30	210

Number 1	Number 2	LCM
6	30	30
7	30	210
8	30	120
9	30	90
10	30	30
11	30	330
12	30	60
13	30	390
14	30	210
15	30	30
16	30	240
17	30	510
18	30	90
19	30	570
20	30	60
21	30	210
22	30	330
23	30	690
24	30	120
25	30	150
26	30	390
27	30	270
28	30	420
29	30	870
30	30	30
31	30	930
32	30	480
33	30	330
34	30	510
35	30	210