LCM for 42 and 28

"Least Common Multiple" Calculator

Least Common Multiple of

and

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

Answer: LCM of 42 and 28 is 84

(Eighty-four)

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

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

LCM = (Number1 × Number2) ÷ GCF

GCF of numbers 42 and 28 is 14, so

LCM = (42 × 28) ÷ 14

LCM = 1176 ÷ 14

LCM = 84

Finding LCM for 42 and 28 by Listing Multiples

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

Multiples of 42: 42, 84, 126, 168

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

So the LCM for 42 and 28 is 84

Finding LCM for 42 and 28 by Prime Factorization

Another method to find LCM for numbers 42 and 28 is to list all Prime Factors for both numbers and multiply the highest exponent prime factors:

All Prime Factors of 42: 2, 3, 7 (exponent form: 21, 31, 71)

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

22 × 31 × 71 = 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 42 and 28? (The answer is: 84). Select the first number (e.g. '42') and the second number (e.g. '28'). 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

Least Common Multiple of

and

LCM Table

Number 1Number 2LCM
2728756
282828
2928812
3028420
3128868
3228224
3328924
3428476
3528140
3628252
37281036
3828532
39281092
4028280
41281148
422884
43281204
4428308
45281260
4628644
47281316
4828336
4928196
5028700
51281428
5228364
53281484
5428756
55281540
562856

FAQ

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

LCM of 42 and 28 is 84

See Also