What is the LCM of 28 and 105?

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What's the Least Common Multiple (LCM) of 28 and 105?

Answer: LCM of 28 and 105 is 420

(Four hundred twenty)

Finding LCM for 28 and 105 using GCF's of these numbers

The first method to find LCM for numbers 28 and 105 is to find Greatest Common Factor (GCF) of these numbers. Here's the formula:

LCM = (Number1 × Number2) ÷ GCF

GCF of numbers 28 and 105 is 7, so

LCM = (28 × 105) ÷ 7

LCM = 2940 ÷ 7

LCM = 420

Finding LCM for 28 and 105 by Listing Multiples

The second method to find LCM for numbers 28 and 105 is to list out the common multiples for both nubmers and pick the first which matching:

Multiples of 28: 28, 56, 84, 112, 140, 168, 196, 224, 252, 280, 308, 336, 364, 392, 420, 448, 476

Multiples of 105: 105, 210, 315, 420, 525, 630

So the LCM for 28 and 105 is 420

Finding LCM for 28 and 105 by Prime Factorization

Another method to find LCM for numbers 28 and 105 is to list all Prime Factors for both numbers and multiply the highest exponent prime factors:

All Prime Factors of 28: 2, 2, 7 (exponent form: 2², 7¹)

All Prime Factors of 105: 3, 5, 7 (exponent form: 3¹, 5¹, 7¹)

2² × 7¹ × 3¹ × 5¹ = 420

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What is the GCF of 28 and 105

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 28 and 105? (The answer is: 420). Select the first number (e.g. '28') and the second number (e.g. '105'). 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

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LCM Table

Number 1	Number 2	LCM
13	105	1365
14	105	210
15	105	105
16	105	1680
17	105	1785
18	105	630
19	105	1995
20	105	420
21	105	105
22	105	2310
23	105	2415
24	105	840
25	105	525
26	105	2730
27	105	945
28	105	420
29	105	3045
30	105	210
31	105	3255
32	105	3360
33	105	1155
34	105	3570
35	105	105
36	105	1260
37	105	3885
38	105	3990
39	105	1365
40	105	840
41	105	4305
42	105	210

LCM for 28 and 105

"Least Common Multiple" Calculator

What's the Least Common Multiple (LCM) of 28 and 105?

Finding LCM for 28 and 105 using GCF's of these numbers

Finding LCM for 28 and 105 by Listing Multiples

Finding LCM for 28 and 105 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 28 and 105?

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