Created By : Jatin Gogia
Reviewed By : Rajasekhar Valipishetty
Last Updated : Apr 06, 2023
Free LCM Calculator determines the least common multiple (LCM) between 1980 and 1985 the smallest integer that is 786060 that is divisible by both numbers.
Least Common Multiple (LCM) of 1980 and 1985 is 786060.
LCM(1980,1985) = 786060
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 1980 and 1985. First we will calculate the prime factors of 1980 and 1985.
Prime Factorization of 1980
2 | 1980 |
2 | 990 |
3 | 495 |
3 | 165 |
5 | 55 |
11 | 11 |
1 |
Prime factors of 1980 are 2, 3, 5,11. Prime factorization of 1980 in exponential form is:
1980 = 22×32×51×111
Prime Factorization of 1985
5 | 1985 |
397 | 397 |
1 |
Prime factors of 1985 are 5,397. Prime factorization of 1985 in exponential form is:
1985 = 51×3971
Now multiplying the highest exponent prime factors to calculate the LCM of 1980 and 1985.
LCM(1980,1985) = 22×32×51×111×3971
LCM(1980,1985) = 786060
Factors of 1980
List of positive integer factors of 1980 that divides 1980 without a remainder.
1, 2, 3, 4, 5, 6, 9, 10, 11, 12, 15, 18, 20, 22, 30, 33, 36, 44, 45, 55, 60, 66, 90, 99, 110, 132, 165, 180, 198, 220, 330, 396, 495, 660, 990, 1980
Factors of 1985
List of positive integer factors of 1985 that divides 1985 without a remainder.
1, 5, 397, 1985
The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 1980 and 1985, than apply into the LCM equation.
GCF(1980,1985) = 5
LCM(1980,1985) = ( 1980 × 1985) / 5
LCM(1980,1985) = 3930300 / 5
LCM(1980,1985) = 786060
(i) The LCM of 1985 and 1980 is associative
LCM of 1980 and 1985 = LCM of 1985 and 1980
1. What is the LCM of 1980 and 1985?
Answer: LCM of 1980 and 1985 is 786060.
2. What are the Factors of 1980?
Answer: Factors of 1980 are 1, 2, 3, 4, 5, 6, 9, 10, 11, 12, 15, 18, 20, 22, 30, 33, 36, 44, 45, 55, 60, 66, 90, 99, 110, 132, 165, 180, 198, 220, 330, 396, 495, 660, 990, 1980. There are 36 integers that are factors of 1980. The greatest factor of 1980 is 1980.
3. What are the Factors of 1985?
Answer: Factors of 1985 are 1, 5, 397, 1985. There are 4 integers that are factors of 1985. The greatest factor of 1985 is 1985.
4. How to Find the LCM of 1980 and 1985?
Answer:
Least Common Multiple of 1980 and 1985 = 786060
Step 1: Find the prime factorization of 1980
1980 = 2 x 2 x 3 x 3 x 5 x 11
Step 2: Find the prime factorization of 1985
1985 = 5 x 397
Step 3: Multiply each factor the greater number of times it occurs in steps i) or ii) above to find the lcm:
LCM = 786060 = 2 x 2 x 3 x 3 x 5 x 11 x 397
Step 4: Therefore, the least common multiple of 1980 and 1985 is 786060.