LCM of 28 and 35

LCM of 28 and 35 is the smallest number among all common multiples of 28 and 35. The first few multiples of 28 and 35 are (28, 56, 84, 112, 140, 168, 196, . . . ) and (35, 70, 105, 140, 175, . . . ) respectively. There are 3 commonly used methods to find LCM of 28 and 35 - by listing multiples, by prime factorization, and by division method.

Answer: LCM of 28 and 35 is 140.

Explanation:

The LCM of two non-zero integers, x(28) and y(35), is the smallest positive integer m(140) that is divisible by both x(28) and y(35) without any remainder.

The methods to find the LCM of 28 and 35 are explained below.

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

LCM of 28 and 35 by Division Method

To calculate the LCM of 28 and 35 by the division method, we will divide the numbers(28, 35) by their prime factors (preferably common). The product of these divisors gives the LCM of 28 and 35.

• Step 1: Find the smallest prime number that is a factor of at least one of the numbers, 28 and 35. Write this prime number(2) on the left of the given numbers(28 and 35), separated as per the ladder arrangement.
• Step 2: If any of the given numbers (28, 35) 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 28 and 35 is the product of all prime numbers on the left, i.e. LCM(28, 35) by division method = 2 × 2 × 5 × 7 = 140.

LCM of 28 and 35 by Listing Multiples

To calculate the LCM of 28 and 35 by listing out the common multiples, we can follow the given below steps:

• Step 1: List a few multiples of 28 (28, 56, 84, 112, 140, 168, 196, . . . ) and 35 (35, 70, 105, 140, 175, . . . . )
• Step 2: The common multiples from the multiples of 28 and 35 are 140, 280, . . .
• Step 3: The smallest common multiple of 28 and 35 is 140.

∴ The least common multiple of 28 and 35 = 140.

LCM of 28 and 35 by Prime Factorization

Prime factorization of 28 and 35 is (2 × 2 × 7) = 2² × 7¹ and (5 × 7) = 5¹ × 7¹ respectively. LCM of 28 and 35 can be obtained by multiplying prime factors raised to their respective highest power, i.e. 2² × 5¹ × 7¹ = 140.
Hence, the LCM of 28 and 35 by prime factorization is 140.

☛ Also Check:

• LCM of 8, 12 and 16 - 48
• LCM of 10 and 16 - 80
• LCM of 108 and 144 - 432
• LCM of 40 and 60 - 120
• LCM of 404 and 96 - 9696
• LCM of 9 and 10 - 90
• LCM of 10 and 50 - 50

FAQs on LCM of 28 and 35

What is the LCM of 28 and 35?

The LCM of 28 and 35 is 140. To find the LCM of 28 and 35, we need to find the multiples of 28 and 35 (multiples of 28 = 28, 56, 84, 112 . . . . 140; multiples of 35 = 35, 70, 105, 140) and choose the smallest multiple that is exactly divisible by 28 and 35, i.e., 140.

What is the Least Perfect Square Divisible by 28 and 35?

The least number divisible by 28 and 35 = LCM(28, 35)
LCM of 28 and 35 = 2 × 2 × 5 × 7 [Incomplete pair(s): 5, 7]
⇒ Least perfect square divisible by each 28 and 35 = LCM(28, 35) × 5 × 7 = 4900 [Square root of 4900 = √4900 = ±70]
Therefore, 4900 is the required number.

If the LCM of 35 and 28 is 140, Find its GCF.

LCM(35, 28) × GCF(35, 28) = 35 × 28
Since the LCM of 35 and 28 = 140
⇒ 140 × GCF(35, 28) = 980
Therefore, the greatest common factor (GCF) = 980/140 = 7.

Which of the following is the LCM of 28 and 35? 32, 140, 50, 36

The value of LCM of 28, 35 is the smallest common multiple of 28 and 35. The number satisfying the given condition is 140.

How to Find the LCM of 28 and 35 by Prime Factorization?

To find the LCM of 28 and 35 using prime factorization, we will find the prime factors, (28 = 2 × 2 × 7) and (35 = 5 × 7). LCM of 28 and 35 is the product of prime factors raised to their respective highest exponent among the numbers 28 and 35.
⇒ LCM of 28, 35 = 2² × 5¹ × 7¹ = 140.