What is the LCM of 28 and 40?

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What's the Least Common Multiple (LCM) of 28 and 40?

Answer: LCM of 28 and 40 is 280

(Two hundred eighty)

Finding LCM for 28 and 40 using GCF's of these numbers

The first method to find LCM for numbers 28 and 40 is to find Greatest Common Factor (GCF) of these numbers. Here's the formula:

LCM = (Number1 × Number2) ÷ GCF

GCF of numbers 28 and 40 is 4, so

LCM = (28 × 40) ÷ 4

LCM = 1120 ÷ 4

LCM = 280

Finding LCM for 28 and 40 by Listing Multiples

The second method to find LCM for numbers 28 and 40 is to list out the common multiples for both nubmers and pick the first which matching:

Multiples of 28: 28, 56, 84, 112, 140, 168, 196, 224, 252, 280, 308, 336

Multiples of 40: 40, 80, 120, 160, 200, 240, 280, 320, 360

So the LCM for 28 and 40 is 280

Finding LCM for 28 and 40 by Prime Factorization

Another method to find LCM for numbers 28 and 40 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 40: 2, 2, 2, 5 (exponent form: 2³, 5¹)

2³ × 7¹ × 5¹ = 280

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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 40? (The answer is: 280). Select the first number (e.g. '28') and the second number (e.g. '40'). 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	40	520
14	40	280
15	40	120
16	40	80
17	40	680
18	40	360
19	40	760
20	40	40
21	40	840
22	40	440
23	40	920
24	40	120
25	40	200
26	40	520
27	40	1080
28	40	280
29	40	1160
30	40	120
31	40	1240
32	40	160
33	40	1320
34	40	680
35	40	280
36	40	360
37	40	1480
38	40	760
39	40	1560
40	40	40
41	40	1640
42	40	840

LCM for 28 and 40

"Least Common Multiple" Calculator

What's the Least Common Multiple (LCM) of 28 and 40?

Finding LCM for 28 and 40 using GCF's of these numbers

Finding LCM for 28 and 40 by Listing Multiples

Finding LCM for 28 and 40 by Prime Factorization

Related Calculations

About "Least Common Multiple" Calculator

"Least Common Multiple" Calculator

LCM Table

FAQ

What's the Least Common Multiple (LCM) of 28 and 40?

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