LCM Of Multiple Numbers By Exponents Using Division

Step A: Find the Factors Using Division

Factor Methods
Factors of 18
2
18
18/2=9
3
9
9/3=3
3
3
3/3=1
1
Factors of 24
2
24
24/2=12
2
12
12/2=6
2
6
6/2=3
3
3
3/3=1
1
Factors of 54
2
54
54/2=27
3
27
27/3=9
3
9
9/3=3
3
3
3/3=1
1
Factors of 60
2
60
60/2=30
2
30
30/2=15
3
15
15/3=5
5
5
5/5=1
1

Division Help

1. Start with the smallest prime.
2. Divide the number by this prime.
3. Write the quotient below.
4. Repeat until the quotient is 1.
5. Confirm using multiplication.

What is Division?

The division method for finding factors begins by dividing the given number by the smallest prime factor like 2, 3,.. This process is repeated with successive primes until the quotient is 1.

Step B: Find the LCM Using Exponents

LCM Method
Calculate LCM
18
=
2
1
×
3
2
24
=
2
3
×
3
1
54
=
2
1
×
3
3
60
=
2
2
×
3
1
×
5
1

Exponents Help

1. List the Prime Factors with power.
2. Identify Unique Prime Factors.
3. Select factors with high power.
4. Multiply to Find LCM.

What is Exponents?

Exponents method simplifies finding the lowest common multiple or LCM by listing all the prime factors of each number and then selecting the highest power of each common prime factor to obtain the LCM.

Solved Examples

Examples

Example 1: Find the LCM of 16, 24 and 32.
Solution:
Prime factorization of 16: 16 = 2, 2, 2, 2
Prime factorization of 24: 24 = 2, 2, 2, 3
Prime factorization of 32: 32 = 2, 2, 2, 2, 2
Take the highest power of each prime factor and multiply them together to get LCM.
Therefore, LCM(16, 24, 32) = 96.
Example 2: Find the LCM of 5, 10 and 15.
Solution:
Prime factorization of 5: 5 = 5
Prime factorization of 10: 10 = 2, 5
Prime factorization of 15: 15 = 3, 5
Take the highest power of each prime factor and multiply them together to get LCM.
Therefore, LCM(5, 10, 15) = 30.
Example 3: Find the LCM of 7, 14 and 21.
Solution:
Prime factorization of 7: 7 = 7
Prime factorization of 14: 14 = 2, 7
Prime factorization of 21: 21 = 3, 7
Take the highest power of each prime factor and multiply them together to get LCM.
Therefore, LCM(7, 14, 21) = 42.

Exercise

Least Common Multiple (LCM)

What is LCM?

LCM or Least Common Multiple, is the smallest number that is divisible by each of the given numbers without leaving a remainder.
The LCM formula can be expressed as,
LCM Formula:
LCM = (a × b)/ HCF(a,b)
where, a and b = Two terms
HCF(a, b) = Highest common factor of a and b.

How to find LCM?

The Least Common Multiple or LCM can be found using various methods, such as: Prime Factorization MethodDivision MethodListing Multiples MethodLadder MethodExponents MethodVenn Diagram Method

FAQ

What are the steps involved to find LCM?
1. Write down the given numbers.
2. Use the division method to find prime factorization of each number.
3. Identify unique prime factors with highest powers.
4. Multiply these factors to find the LCM.
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