Read this article to figure out how to calculate the lowest common denominator of . Learn the two different methods that you can use to find the LCD: the prime factorization method and the LCD formula method. We will explain both these methods in detail so stick around until the very end to understand. Utilise our free LCD Calculator to avail the LCD of numbers easily.
Given numbers are 720,280,421
We can find the LCD of numbers 720,280,421 by the prime factorization method or by applying the LCD formula.
The LCD of 720,280,421 is 2121840.
2 | 720, 280, 421 |
2 | 360, 140, 421 |
2 | 180, 70, 421 |
5 | 90, 35, 421 |
18, 7, 421 |
As you can see, now we have to multiply the prime numbers on the left side with the co-primes at the bottom.
2 x 2 x 2 x 5 x 18 x 7 x 421 = 2121840
Thus, we have determined that the LCD of 720,280,421 is 2121840
The LCD formula is LCD(a,b) = ( a x b) / GCF(a,b)
Step1:
Find the GCF of 720 and 280. To find the GCF, list down the factors of 720 and 280 and select the highest factor that appears in both lists of factors.
720 : [1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 16, 18, 20, 24, 30, 36, 40, 45, 48, 60, 72, 80, 90, 120, 144, 180, 240, 360, 720]
280 : [1, 2, 4, 5, 7, 8, 10, 14, 20, 28, 35, 40, 56, 70, 140, 280]
From this, we can see that the GCF of 720 and 280 is 40.
Now, put this into the LCD formula.
LCD(720, 280) = ( 720 x 280 ) / 40
LCD(720, 280) = 201600 / 40
LCD(720, 280) = 5040
Step2:
Find the GCF of 5040 and 421. To find the GCF, list down the factors of 5040 and 421 and select the highest factor that appears in both lists of factors.
5040 : [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 24, 28, 30, 35, 36, 40, 42, 45, 48, 56, 60, 63, 70, 72, 80, 84, 90, 105, 112, 120, 126, 140, 144, 168, 180, 210, 240, 252, 280, 315, 336, 360, 420, 504, 560, 630, 720, 840, 1008, 1260, 1680, 2520, 5040]
421 : [1, 421]
From this, we can see that the GCF of 5040 and 421 is 1.
Now, put this into the LCD formula.
LCD(5040, 421) = ( 5040 x 421 ) / 1
LCD(5040, 421) = 2121840 / 1
LCD(5040, 421) = 2121840
LCD of 720,280,421 is 2121840
Here are some samples of LCD of Numbers calculations.
1. What is the LCD of ?
Answer: LCD of is .
2. How to find LCD of using prime factorization ?
Answer: Just keep dividing by prime numbers until only co-primes are left over. At that point, simply multiply the co-primes with the prime numbers on the left. The answer will be , the LCD.
3. How to Find the LCD of using LCD formula ?
Answer: The LCD formula is LCD(a,b) = ( a x b) / GCF(a,b).
You must first calculate the LCD OF and . Then, find the LCD of that answer and and so on. The answer will be , which is the LCD of .