Created By : Jatin Gogia
Reviewed By : Rajasekhar Valipishetty
Last Updated : Apr 06, 2023
Free LCM Calculator determines the least common multiple (LCM) between 390 and 398 the smallest integer that is 77610 that is divisible by both numbers.
Least Common Multiple (LCM) of 390 and 398 is 77610.
LCM(390,398) = 77610
Least common multiple or lowest common denominator (LCD) can be calculated in three ways;
Least common multiple can be found by multiplying the highest exponent prime factors of 390 and 398. First we will calculate the prime factors of 390 and 398.
Prime Factorization of 390
2 | 390 |
3 | 195 |
5 | 65 |
13 | 13 |
1 |
Prime factors of 390 are 2, 3, 5,13. Prime factorization of 390 in exponential form is:
390 = 21×31×51×131
Prime Factorization of 398
2 | 398 |
199 | 199 |
1 |
Prime factors of 398 are 2,199. Prime factorization of 398 in exponential form is:
398 = 21×1991
Now multiplying the highest exponent prime factors to calculate the LCM of 390 and 398.
LCM(390,398) = 21×31×51×131×1991
LCM(390,398) = 77610
Factors of 390
List of positive integer factors of 390 that divides 390 without a remainder.
1, 2, 3, 5, 6, 10, 13, 15, 26, 30, 39, 65, 78, 130, 195, 390
Factors of 398
List of positive integer factors of 398 that divides 398 without a remainder.
1, 2, 199, 398
The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 390 and 398, than apply into the LCM equation.
GCF(390,398) = 2
LCM(390,398) = ( 390 × 398) / 2
LCM(390,398) = 155220 / 2
LCM(390,398) = 77610
(i) The LCM of 398 and 390 is associative
LCM of 390 and 398 = LCM of 398 and 390
1. What is the LCM of 390 and 398?
Answer: LCM of 390 and 398 is 77610.
2. What are the Factors of 390?
Answer: Factors of 390 are 1, 2, 3, 5, 6, 10, 13, 15, 26, 30, 39, 65, 78, 130, 195, 390. There are 16 integers that are factors of 390. The greatest factor of 390 is 390.
3. What are the Factors of 398?
Answer: Factors of 398 are 1, 2, 199, 398. There are 4 integers that are factors of 398. The greatest factor of 398 is 398.
4. How to Find the LCM of 390 and 398?
Answer:
Least Common Multiple of 390 and 398 = 77610
Step 1: Find the prime factorization of 390
390 = 2 x 3 x 5 x 13
Step 2: Find the prime factorization of 398
398 = 2 x 199
Step 3: Multiply each factor the greater number of times it occurs in steps i) or ii) above to find the lcm:
LCM = 77610 = 2 x 3 x 5 x 13 x 199
Step 4: Therefore, the least common multiple of 390 and 398 is 77610.