LCM for 18 and 42

"Least Common Multiple" Calculator

Least Common Multiple of

and

What's the Least Common Multiple (LCM) of 18 and 42?

Answer

LCM of 18 and 42 is 126

(One hundred twenty-six)

Finding LCM for 18 and 42 using GCF of these numbers

The first method to find LCM for numbers 18 and 42 is to find Greatest Common Factor (GCF) of these numbers. Here's the formula:

LCM = (Number1 × Number2) ÷ GCF

GCF of numbers 18 and 42 is 6, so

LCM = (18 × 42) ÷ 6

LCM = 756 ÷ 6

LCM = 126

Finding LCM for 18 and 42 by Listing Multiples

The second method to find LCM for numbers 18 and 42 is to list out the common multiples for both numbers and pick the first one that matches:

Multiples of 18: 18, 36, 54, 72, 90, 108, 126, 144, 162

Multiples of 42: 42, 84, 126, 168, 210

So the LCM for 18 and 42 is 126

Finding LCM for 18 and 42 by Prime Factorization

Another method to find LCM for numbers 18 and 42 is to list all Prime Factors for both numbers and multiply the highest exponent prime factors:

All Prime Factors of 18: 2, 3, 3 (exponent form: 21, 32)

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

21 × 32 × 71 = 126

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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 18 and 42? (The answer is: 126). Select the first number (e.g. '18') 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

"Least Common Multiple" Calculator

Least Common Multiple of

and

LCM Table

Number 1Number 2LCM
34242
44284
542210
64242
74242
842168
942126
1042210
1142462
124284
1342546
144242
1542210
1642336
1742714
1842126
1942798
2042420
214242
2242462
2342966
2442168
25421050
2642546
2742378
284284
29421218
3042210
31421302
3242672

FAQ

What's the Least Common Multiple (LCM) of 18 and 42?

LCM of 18 and 42 is 126

How to find the LCM of 18 and 42 using prime factorization?

To find the LCM of 18 and 42, find all prime factors of both numbers, then multiply the highest power of each prime factor. The result is 126.

What is the difference between LCM and GCF?

LCM (Least Common Multiple) is the smallest number divisible by both numbers, while GCF (Greatest Common Factor) is the largest number that divides both. For 18 and 42: LCM = 126, GCF = 6.

See Also