LCM for 21 and 105

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Least Common Multiple of
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What's the Least Common Multiple (LCM) of 21 and 105?

Answer

LCM of 21 and 105 is
105

(One hundred five)

Finding LCM for 21 and 105 using GCF of these numbers

The first method to find LCM for numbers 21 and 105 is to find Greatest Common Factor (GCF) of these numbers. Here's the formula:

LCM = (Number1 × Number2) ÷ GCF

GCF of numbers 21 and 105 is 21, so

LCM = (21 × 105) ÷ 21

LCM = 2,205 ÷ 21

LCM = 105

Finding LCM for 21 and 105 by Listing Multiples

The second method to find LCM for numbers 21 and 105 is to list out the common multiples for both numbers and pick the first one that matches:

Multiples of 21: 21, 42, 63, 84, 105, 126, 147

Multiples of 105: 105, 210, 315

So the LCM for 21 and 105 is 105

Finding LCM for 21 and 105 by Prime Factorization

Another method to find LCM for numbers 21 and 105 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 105: 3, 5, 7 (exponent form: 31, 51, 71)

31 × 71 × 51 = 105

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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 105? (The answer is: 105). Select the first number (e.g. '21') 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
"Least Common Multiple" Calculator
Least Common Multiple of
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LCM Table

Number 1Number 2LCM
212884
2129609
2130210
2132672
2133231
2134714
2135105
2136252
2139273
2141861
214242
2143903
2144924
2145315
2147987
2148336
2149147
2151357
21521,092
21531,113
21551,155
2156168
21581,218
21591,239
2160420
2169483
21801,680
218484
211002,100
21105105

FAQ

What's the Least Common Multiple (LCM) of 21 and 105?

LCM of 21 and 105 is 105

How to find the LCM of 21 and 105 using prime factorization?

To find the LCM of 21 and 105, find all prime factors of both numbers, then multiply the highest power of each prime factor. The result is 105.

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 21 and 105: LCM = 105, GCF = 21.

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