LCM for 21 and 24

The first method to find LCM for numbers 21 and 24 is to find Greatest Common Factor (GCF) of these numbers. Here's the formula:

LCM = (Number1 × Number2) ÷ GCF

GCF of numbers 21 and 24 is 3, so

LCM = (21 × 24) ÷ 3

LCM = 504 ÷ 3

LCM = 168

The second method to find LCM for numbers 21 and 24 is to list out the common multiples for both nubmers and pick the first which matching:

Multiples of 21: 21, 42, 63, 84, 105, 126, 147, 168, 189, 210

Multiples of 24: 24, 48, 72, 96, 120, 144, 168, 192, 216

So the LCM for 21 and 24 is 168

Another method to find LCM for numbers 21 and 24 is to list all Prime Factors for both numbers and multiply the highest exponent prime factors: