LCM of 81 and 180
1620 is the LCM of 81 and 180. The step-by-step solution using prime factors and special division methods is one of the simple methods to easily understand how to find what is the LCM of 81 and 180, provided along with the use cases of mathematics and real-world problems.
what is the lcm of 81 and 180?
lcm (81 180) = (?)
81 => 3 x 3 x 3 x 3
180 => 2 x 2 x 3 x 3 x 5
= 3 x 3 x 3 x 3 x 2 x 2 x 5
= 1620
lcm (81 and 180) = 1620
1620 is the LCM of 81 and 180.
where,
81 is a positive integer,
180 is a positive integer,
1620 is the LCM of 81 and 180,
{3 x 3} in {3 x 3 x 3 x 3, 2 x 2 x 3 x 3 x 5} are the common factors of 81 and 180,
{3 x 3 x 2 x 2 x 5} in {3 x 3 x 3 x 3, 2 x 2 x 3 x 3 x 5} are the uncommon factors of 81 and 180.
Use in Mathematics: LCM of 81 and 180
The below are some of the mathematical applications where lcm of 81 and 180 can be used:
- to find the least number which is exactly divisible by 81 and 180.
- to find the common denominator for two fractions having 81 and 180 as denominators in the unlike fractions addition or subtraction.
In the context of lcm real world problems, the lcm of 81 and 180 helps to find the exact time when two similar and recurring events with different time schedule happens together at the same time. For example, the real world problems involve lcm in situations to find at what time the bells A and B all toll together, if bell A tolls at 81 seconds and bell B tolls at 180 seconds repeatedly. The answer is that all bells A and B toll together at 1620 seconds for the first time, at 3240 seconds for the second time, at 4860 seconds for the third time and so on.
Important Notes: 81 and 180 lcm
The below are the important notes to be remembered while solving the lcm of 81 and 180:
- The common prime factors and the remaining prime factors of 81 and 180 should be multiplied to find the least common multiple of 81 and 180, when solving lcm by using prime factors method.
- The results of lcm of 81 and 180, and the lcm of 180 and 81 are identical, it means the order of given numbers in the lcm calculation doesn't affect the results.
How-to: What is the LCM of 81 and 180?
The below solved example with step by step work shows how to find what is the lcm of 81 and 180 by using prime factors method and division method.
Solved example using prime factors method:
What is the LCM of 81 and 180?
step 1
Address the input parameters, values and observe what to be found:
Input parameters and values:
A = 81
B = 180
What to be found:
find the lcm of 81 and 180
step 2 Find the prime factors of 81 and 180:
Prime factors of 81 = 3 x 3 x 3 x 3
Prime factors of 180 = 2 x 2 x 3 x 3 x 5
step 3 Identify the repeated and non-repeated prime factors of 81 and 180:
{3, 3} are the most repeated factors and {3 x 3 x 2 x 2 x 5} are the non-repeated factors of 81 and 180.
step 4 Find the product of repeated and non-repeated prime factors of 81 and 180:
= 3 x 3 x 3 x 3 x 2 x 2 x 5
= 1620
lcm(81 and 180) = 1620
Hence,
lcm of 81 and 180 is 1620
This special division method is one of the easiest ways to understand the entire calculation to find the LCM of 81 and 180.
step 1 Address the input parameters, values and observe what to be found:
Input parameters and values:
Integers: 81 and 180
What to be found:
lcm (81, 180) = ?
step 2 Arrange the given integers in the horizontal form with space or comma separated format:
81 and 180
step 3 Choose the divisor which divides each or most of the given integers (81 and 180), divide each integers separately and write down the quotient in the next line right under the respective integers. Bring down the integer to the next line if any integer in 81 and 180 is not divisible by the selected divisor; repeat the same process until all the integers are brought to 1 as like below:
| 2 | 81 | 180 |
| 2 | 81 | 90 |
| 3 | 81 | 45 |
| 3 | 27 | 15 |
| 3 | 9 | 5 |
| 3 | 3 | 5 |
| 5 | 1 | 5 |
| 1 | 1 |
step 4 Multiply the divisors to find the lcm of 81 and 180:
= 2 x 2 x 3 x 3 x 3 x 3 x 5
= 1620
LCM(81, 180) = 1620
The LCM of two numbers 81 and 180 is 1620