LCM of 8 and 30
LCM of 8 and 30 is the smallest number among all common multiples of 8 and 30. The first few multiples of 8 and 30 are (8, 16, 24, 32, . . . ) and (30, 60, 90, 120, 150, 180, . . . ) respectively. There are 3 commonly used methods to find LCM of 8 and 30 - by division method, by listing multiples, and by prime factorization.
1. | LCM of 8 and 30 |
2. | List of Methods |
3. | Solved Examples |
4. | FAQs |
What is the LCM of 8 and 30?
Answer: LCM of 8 and 30 is 120.
Explanation:
The LCM of two non-zero integers, x(8) and y(30), is the smallest positive integer m(120) that is divisible by both x(8) and y(30) without any remainder.
Methods to Find LCM of 8 and 30
Let's look at the different methods for finding the LCM of 8 and 30.
- By Prime Factorization Method
- By Division Method
- By Listing Multiples
LCM of 8 and 30 by Prime Factorization
Prime factorization of 8 and 30 is (2 × 2 × 2) = 23 and (2 × 3 × 5) = 21 × 31 × 51 respectively. LCM of 8 and 30 can be obtained by multiplying prime factors raised to their respective highest power, i.e. 23 × 31 × 51 = 120.
Hence, the LCM of 8 and 30 by prime factorization is 120.
LCM of 8 and 30 by Division Method
To calculate the LCM of 8 and 30 by the division method, we will divide the numbers(8, 30) by their prime factors (preferably common). The product of these divisors gives the LCM of 8 and 30.
- Step 1: Find the smallest prime number that is a factor of at least one of the numbers, 8 and 30. Write this prime number(2) on the left of the given numbers(8 and 30), separated as per the ladder arrangement.
- Step 2: If any of the given numbers (8, 30) is a multiple of 2, divide it by 2 and write the quotient below it. Bring down any number that is not divisible by the prime number.
- Step 3: Continue the steps until only 1s are left in the last row.
The LCM of 8 and 30 is the product of all prime numbers on the left, i.e. LCM(8, 30) by division method = 2 × 2 × 2 × 3 × 5 = 120.
LCM of 8 and 30 by Listing Multiples
To calculate the LCM of 8 and 30 by listing out the common multiples, we can follow the given below steps:
- Step 1: List a few multiples of 8 (8, 16, 24, 32, . . . ) and 30 (30, 60, 90, 120, 150, 180, . . . . )
- Step 2: The common multiples from the multiples of 8 and 30 are 120, 240, . . .
- Step 3: The smallest common multiple of 8 and 30 is 120.
∴ The least common multiple of 8 and 30 = 120.
☛ Also Check:
- LCM of 10, 15 and 20 - 60
- LCM of 150 and 180 - 900
- LCM of 56 and 84 - 168
- LCM of 30 and 42 - 210
- LCM of 10, 20 and 25 - 100
- LCM of 60, 84 and 108 - 3780
- LCM of 3 and 15 - 15
LCM of 8 and 30 Examples
-
Example 1: The product of two numbers is 240. If their GCD is 2, what is their LCM?
Solution:
Given: GCD = 2
product of numbers = 240
∵ LCM × GCD = product of numbers
⇒ LCM = Product/GCD = 240/2
Therefore, the LCM is 120.
The probable combination for the given case is LCM(8, 30) = 120. -
Example 2: Verify the relationship between GCF and LCM of 8 and 30.
Solution:
The relation between GCF and LCM of 8 and 30 is given as,
LCM(8, 30) × GCF(8, 30) = Product of 8, 30
Prime factorization of 8 and 30 is given as, 8 = (2 × 2 × 2) = 23 and 30 = (2 × 3 × 5) = 21 × 31 × 51
LCM(8, 30) = 120
GCF(8, 30) = 2
LHS = LCM(8, 30) × GCF(8, 30) = 120 × 2 = 240
RHS = Product of 8, 30 = 8 × 30 = 240
⇒ LHS = RHS = 240
Hence, verified. -
Example 3: Find the smallest number that is divisible by 8 and 30 exactly.
Solution:
The smallest number that is divisible by 8 and 30 exactly is their LCM.
⇒ Multiples of 8 and 30:- Multiples of 8 = 8, 16, 24, 32, 40, 48, 56, 64, 72, 80, 88, 96, 104, 112, 120, . . . .
- Multiples of 30 = 30, 60, 90, 120, 150, . . . .
Therefore, the LCM of 8 and 30 is 120.
FAQs on LCM of 8 and 30
What is the LCM of 8 and 30?
The LCM of 8 and 30 is 120. To find the least common multiple of 8 and 30, we need to find the multiples of 8 and 30 (multiples of 8 = 8, 16, 24, 32 . . . . 120; multiples of 30 = 30, 60, 90, 120) and choose the smallest multiple that is exactly divisible by 8 and 30, i.e., 120.
What are the Methods to Find LCM of 8 and 30?
The commonly used methods to find the LCM of 8 and 30 are:
- Prime Factorization Method
- Listing Multiples
- Division Method
What is the Relation Between GCF and LCM of 8, 30?
The following equation can be used to express the relation between GCF and LCM of 8 and 30, i.e. GCF × LCM = 8 × 30.
If the LCM of 30 and 8 is 120, Find its GCF.
LCM(30, 8) × GCF(30, 8) = 30 × 8
Since the LCM of 30 and 8 = 120
⇒ 120 × GCF(30, 8) = 240
Therefore, the greatest common factor (GCF) = 240/120 = 2.
How to Find the LCM of 8 and 30 by Prime Factorization?
To find the LCM of 8 and 30 using prime factorization, we will find the prime factors, (8 = 2 × 2 × 2) and (30 = 2 × 3 × 5). LCM of 8 and 30 is the product of prime factors raised to their respective highest exponent among the numbers 8 and 30.
⇒ LCM of 8, 30 = 23 × 31 × 51 = 120.
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