LCM for 28 and 40
What's the Least Common Multiple (LCM) of 28 and 40?
(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
Related Calculations
See Also
- Greatest Common Factor - Find the Greatest Common Factor (GCF) of two numbers
<a href="https://calculat.io/en/number/least-common-multiple-lcm-of/28--40">What is the LCM of 28 and 40? - Calculatio</a>
LCM Table
About "Least Common Multiple" Calculator
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