LCM of 5 and 9

LCM of 5 and 9 is the smallest number among all common multiples of 5 and 9. The first few multiples of 5 and 9 are (5, 10, 15, 20, 25, 30, . . . ) and (9, 18, 27, 36, 45, 54, 63, . . . ) respectively. There are 3 commonly used methods to find LCM of 5 and 9 - by division method, by listing multiples, and by prime factorization.

Answer: LCM of 5 and 9 is 45.

Explanation:

The LCM of two non-zero integers, x(5) and y(9), is the smallest positive integer m(45) that is divisible by both x(5) and y(9) without any remainder.

Let's look at the different methods for finding the LCM of 5 and 9.

• By Prime Factorization Method
• By Division Method
• By Listing Multiples

LCM of 5 and 9 by Prime Factorization

Prime factorization of 5 and 9 is (5) = 5¹ and (3 × 3) = 3² respectively. LCM of 5 and 9 can be obtained by multiplying prime factors raised to their respective highest power, i.e. 3² × 5¹ = 45.
Hence, the LCM of 5 and 9 by prime factorization is 45.

LCM of 5 and 9 by Division Method

To calculate the LCM of 5 and 9 by the division method, we will divide the numbers(5, 9) by their prime factors (preferably common). The product of these divisors gives the LCM of 5 and 9.

• Step 1: Find the smallest prime number that is a factor of at least one of the numbers, 5 and 9. Write this prime number(3) on the left of the given numbers(5 and 9), separated as per the ladder arrangement.
• Step 2: If any of the given numbers (5, 9) is a multiple of 3, divide it by 3 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 5 and 9 is the product of all prime numbers on the left, i.e. LCM(5, 9) by division method = 3 × 3 × 5 = 45.

LCM of 5 and 9 by Listing Multiples

To calculate the LCM of 5 and 9 by listing out the common multiples, we can follow the given below steps:

• Step 1: List a few multiples of 5 (5, 10, 15, 20, 25, 30, . . . ) and 9 (9, 18, 27, 36, 45, 54, 63, . . . . )
• Step 2: The common multiples from the multiples of 5 and 9 are 45, 90, . . .
• Step 3: The smallest common multiple of 5 and 9 is 45.

∴ The least common multiple of 5 and 9 = 45.

☛ Also Check:

• LCM of 16 and 64 - 64
• LCM of 4, 5 and 10 - 20
• LCM of 45 and 54 - 270
• LCM of 35, 12 and 70 - 420
• LCM of 144 and 169 - 24336
• LCM of 8 and 36 - 72
• LCM of 15 and 27 - 135

FAQs on LCM of 5 and 9

What is the LCM of 5 and 9?

The LCM of 5 and 9 is 45. To find the least common multiple of 5 and 9, we need to find the multiples of 5 and 9 (multiples of 5 = 5, 10, 15, 20 . . . . 45; multiples of 9 = 9, 18, 27, 36 . . . . 45) and choose the smallest multiple that is exactly divisible by 5 and 9, i.e., 45.

What is the Least Perfect Square Divisible by 5 and 9?

The least number divisible by 5 and 9 = LCM(5, 9)
LCM of 5 and 9 = 3 × 3 × 5 [Incomplete pair(s): 5]
⇒ Least perfect square divisible by each 5 and 9 = LCM(5, 9) × 5 = 225 [Square root of 225 = √225 = ±15]
Therefore, 225 is the required number.

How to Find the LCM of 5 and 9 by Prime Factorization?

To find the LCM of 5 and 9 using prime factorization, we will find the prime factors, (5 = 5) and (9 = 3 × 3). LCM of 5 and 9 is the product of prime factors raised to their respective highest exponent among the numbers 5 and 9.
⇒ LCM of 5, 9 = 3² × 5¹ = 45.

What are the Methods to Find LCM of 5 and 9?

The commonly used methods to find the LCM of 5 and 9 are:

• Prime Factorization Method
• Division Method
• Listing Multiples

If the LCM of 9 and 5 is 45, Find its GCF.

LCM(9, 5) × GCF(9, 5) = 9 × 5
Since the LCM of 9 and 5 = 45
⇒ 45 × GCF(9, 5) = 45
Therefore, the GCF = 45/45 = 1.