The least common multiple (LCM) of 18 and 30 is 90. The LCM is the smallest positive integer that is evenly divisible by two or more integers. To calculate the LCM of 18 and 30, list the prime factors of each number and then multiply each factor the greatest number of times it appears in either number.
For 18:
2 x 3 x 3 = 18
For 30:
2 x 3 x 5 = 30
The greatest number of times each factor appears is 3 for 2, 3 and 5.
Therefore the LCM = 2 x 3 x 3 x 5 = 90.
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How do you find the LCM of 18?
The least common multiple (LCM) of two or more numbers is the smallest number that is a multiple of all of the numbers. To find the LCM of 18, you need to determine the prime factorization of 18. 18 = 2 × 3 × 3 = 2^1 × 3^2.
Now the LCM of 18 is the product of the highest power of each prime number found in the prime factorization process. Thus, the LCM of 18 is 2^1 × 3^2 which is equal to 18 × 3 = 54. Therefore, the LCM of 18 is 54.
What are factors of 18 30?
The factors of 18 are 1, 2, 3, 6, 9, 18. The factors of 30 are 1, 2, 3, 5, 6, 10, 15, 30. All the factors of 18 and 30 are 1, 2, 3, 5, 6, 9, 10, 15, 18, 30.
What is the LCM of 18 and 21 using prime factorization?
The LCM (Lowest Common Multiple) of 18 and 21 is 126 when found using prime factorization. To do this, the given numbers are first expressed as their prime factors.
18 = 2 * 3 * 3
21 = 3 * 7
The prime factors of each numbe are then listed.
2, 3, 3, 7
The list is then rearranged so that all the prime factors are expressed in descending order.
7, 3, 3, 2
The LCM is then calculated by multiplying each prime factor the greatest number of times it appears in either number.
LCM = 7 * 3 * 3 * 2 = 126
How is 18 a composite number?
18 is a composite number because it is a whole number that is greater than 1 and has multiple factors other than itself and one. 18 can be divided evenly by 1, 2, 3, 6, 9, and 18. This means it is not a prime number, and thus it is a composite number.
When a number has more than two factors it is said to be a composite number.
What is the prime factorization of 18 *?
The prime factorization of 18 is 2 x 3 x 3, which can also be written as 2 x 3². This can be determined by dividing 18 by any prime number, beginning with 2. When divided by 2, 18 divided by 2 is 9. Then, dividing 9 by 3, we find that 9 divided by 3 is 3.
3 cannot be divided any further, which indicates that the prime factors of 18 are 2 x 3 x 3, or 2 x 3².
