LCM for 40 and 84
What's the Least Common Multiple (LCM) of 40 and 84?
(Eight hundred forty)
Finding LCM for 40 and 84 using GCF's of these numbers
The first method to find LCM for numbers 40 and 84 is to find Greatest Common Factor (GCF) of these numbers. Here's the formula:
LCM = (Number1 × Number2) ÷ GCF
GCF of numbers 40 and 84 is 4, so
LCM = (40 × 84) ÷ 4
LCM = 3360 ÷ 4
LCM = 840
Finding LCM for 40 and 84 by Listing Multiples
The second method to find LCM for numbers 40 and 84 is to list out the common multiples for both nubmers and pick the first which matching:
Multiples of 40: 40, 80, 120, 160, 200, 240, 280, 320, 360, 400, 440, 480, 520, 560, 600, 640, 680, 720, 760, 800, 840, 880, 920
Multiples of 84: 84, 168, 252, 336, 420, 504, 588, 672, 756, 840, 924, 1008
So the LCM for 40 and 84 is 840
Finding LCM for 40 and 84 by Prime Factorization
Another method to find LCM for numbers 40 and 84 is to list all Prime Factors for both numbers and multiply the highest exponent prime factors:
All Prime Factors of 40: 2, 2, 2, 5 (exponent form: 23, 51)
All Prime Factors of 84: 2, 2, 3, 7 (exponent form: 22, 31, 71)
23 × 51 × 31 × 71 = 840
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/40--84">What is the LCM of 40 and 84? - 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