What is the LCM of 28 and 42?

"Least Common Multiple" Calculator

What's the Least Common Multiple (LCM) of 28 and 42?

Answer: LCM of 28 and 42 is 84

(Eighty-four)

Finding LCM for 28 and 42 using GCF's of these numbers

The first method to find LCM for numbers 28 and 42 is to find Greatest Common Factor (GCF) of these numbers. Here's the formula:

LCM = (Number1 × Number2) ÷ GCF

GCF of numbers 28 and 42 is 14, so

LCM = (28 × 42) ÷ 14

LCM = 1176 ÷ 14

LCM = 84

Finding LCM for 28 and 42 by Listing Multiples

The second method to find LCM for numbers 28 and 42 is to list out the common multiples for both nubmers and pick the first which matching:

Multiples of 28: 28, 56, 84, 112, 140

Multiples of 42: 42, 84, 126, 168

So the LCM for 28 and 42 is 84

Finding LCM for 28 and 42 by Prime Factorization

Another method to find LCM for numbers 28 and 42 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 42: 2, 3, 7 (exponent form: 2¹, 3¹, 7¹)

2² × 7¹ × 3¹ = 84

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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 28 and 42? (The answer is: 84). Select the first number (e.g. '28') and the second number (e.g. '42'). 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	42	546
14	42	42
15	42	210
16	42	336
17	42	714
18	42	126
19	42	798
20	42	420
21	42	42
22	42	462
23	42	966
24	42	168
25	42	1050
26	42	546
27	42	378
28	42	84
29	42	1218
30	42	210
31	42	1302
32	42	672
33	42	462
34	42	714
35	42	210
36	42	252
37	42	1554
38	42	798
39	42	546
40	42	840
41	42	1722
42	42	42

LCM for 28 and 42

"Least Common Multiple" Calculator

What's the Least Common Multiple (LCM) of 28 and 42?

Finding LCM for 28 and 42 using GCF's of these numbers

Finding LCM for 28 and 42 by Listing Multiples

Finding LCM for 28 and 42 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 42?

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