LCM for 5, 20 and 25

"Least Common Multiple of 3 Numbers" Calculator
Least Common Multiple of
,
and

What's the Least Common Multiple (LCM) of 5, 20 and 25?

Answer

LCM of 5, 20 and 25 is
100

(One hundred)

100 is the smallest positive integer that 5, 20 and 25 all divide without a remainder — every other common multiple of the three is a multiple of it.

Finding the LCM of 5, 20 and 25 by Prime Factorization

Split all three numbers into prime factors, then take every prime that shows up in at least one of them, each raised to the highest power it reaches there. Multiplying those highest powers gives the least common multiple:

All Prime Factors of 5: 5 (exponent form: 5)

All Prime Factors of 20: 2 × 2 × 5 (exponent form: 22 × 5)

All Prime Factors of 25: 5 × 5 (exponent form: 52)

Prime factor52025Highest power
2—22—22
5555252

LCM = 22 × 52 = 100

Checking the LCM of 5, 20 and 25 Two Numbers at a Time

The least common multiple is associative, so three numbers can be handled as two pairs: first the LCM of the first two, then the LCM of that value and the third. Each pair goes through the two-number formula, which uses the greatest common divisor:

LCM(a, b) = (a × b) ÷ GCD(a, b)

LCM(5, 20) = (5 × 20) ÷ 5 = 100 ÷ 5 = 20

LCM(20, 25) = (20 × 25) ÷ 5 = 500 ÷ 5 = 100

LCM(5, 20, 25) = 100

The pairs may be taken in any order — 20 and 25 first, then 5 — and the answer is the same 100. That is exactly why the two routes on this page agree.

Related Calculations

See Also

About "Least Common Multiple of 3 Numbers" Calculator

This calculator finds the Least Common Multiple (LCM) of three numbers at once, without doing it in two passes. For example, it can help you find out what's the Least Common Multiple (LCM) of 5, 20 and 25? (The answer is: 100). Enter the first number (e.g. '5'), the second (e.g. '20') and the third (e.g. '25'), then hit the 'Calculate' button.
The Least Common Multiple of three numbers is the smallest positive integer that all three of them divide without a remainder
"Least Common Multiple of 3 Numbers" Calculator
Least Common Multiple of
,
and

LCM Table

Number 1Number 2Number 3LCM
5102020
51120220
5122060
51320260
51420140
5152060
5162080
51720340
51820180
51920380
5202020
52021420
52022220
52023460
52024120
52025100
52026260
52027540
52028140
52029580
5203060
52031620
52032160
52033660
52034340
52035140
52036180
52037740
52038380
52039780

FAQ

What's the Least Common Multiple (LCM) of 5, 20 and 25?

LCM of 5, 20 and 25 is 100

How to find the LCM of 5, 20 and 25 by prime factorization?

Take every prime that appears in 5, 20 and 25 to the highest power it reaches in any one of them and multiply: 2² × 5² = 100.

Can you get the LCM of 5, 20 and 25 two numbers at a time?

Yes, and it is the check this page prints. The LCM of 5 and 20 is 20, and the LCM of 20 and 25 is 100 — the same answer, because the least common multiple is associative and does not depend on the order of the three numbers.

Is 100 divisible by 5, 20 and 25?

Yes, and by definition it is the smallest positive integer that is: 100 ÷ 5, 100 ÷ 20 and 100 ÷ 25 all come out whole. Any other common multiple of 5, 20 and 25 is a multiple of 100.

See Also