Created By : Jatin Gogia
Reviewed By : Rajasekhar Valipishetty
Last Updated : Apr 06, 2023
Free LCM Calculator determines the least common multiple (LCM) between 87 and 90 the smallest integer that is 2610 that is divisible by both numbers.
Least Common Multiple (LCM) of 87 and 90 is 2610.
LCM(87,90) = 2610
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 87 and 90. First we will calculate the prime factors of 87 and 90.
Prime Factorization of 87
3 | 87 |
29 | 29 |
1 |
Prime factors of 87 are 3,29. Prime factorization of 87 in exponential form is:
87 = 31×291
Prime Factorization of 90
2 | 90 |
3 | 45 |
3 | 15 |
5 | 5 |
1 |
Prime factors of 90 are 2, 3,5. Prime factorization of 90 in exponential form is:
90 = 21×32×51
Now multiplying the highest exponent prime factors to calculate the LCM of 87 and 90.
LCM(87,90) = 21×32×51×291
LCM(87,90) = 2610
Factors of 87
List of positive integer factors of 87 that divides 87 without a remainder.
1, 3, 29, 87
Factors of 90
List of positive integer factors of 90 that divides 90 without a remainder.
1, 2, 3, 5, 6, 9, 10, 15, 18, 30, 45, 90
The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 87 and 90, than apply into the LCM equation.
GCF(87,90) = 3
LCM(87,90) = ( 87 × 90) / 3
LCM(87,90) = 7830 / 3
LCM(87,90) = 2610
(i) The LCM of 90 and 87 is associative
LCM of 87 and 90 = LCM of 90 and 87
1. What is the LCM of 87 and 90?
Answer: LCM of 87 and 90 is 2610.
2. What are the Factors of 87?
Answer: Factors of 87 are 1, 3, 29, 87. There are 4 integers that are factors of 87. The greatest factor of 87 is 87.
3. What are the Factors of 90?
Answer: Factors of 90 are 1, 2, 3, 5, 6, 9, 10, 15, 18, 30, 45, 90. There are 12 integers that are factors of 90. The greatest factor of 90 is 90.
4. How to Find the LCM of 87 and 90?
Answer:
Least Common Multiple of 87 and 90 = 2610
Step 1: Find the prime factorization of 87
87 = 3 x 29
Step 2: Find the prime factorization of 90
90 = 2 x 3 x 3 x 5
Step 3: Multiply each factor the greater number of times it occurs in steps i) or ii) above to find the lcm:
LCM = 2610 = 2 x 3 x 3 x 5 x 29
Step 4: Therefore, the least common multiple of 87 and 90 is 2610.