# 21, 72 and 94 LCM

LCM of 21, 72 and 94 is equal to 23688. The comprehensive work provides more insight of how to find what is the lcm of 21, 72 and 94 by using prime factors and special division methods, and the example use case of mathematics and real world problems.

__what is the lcm of 21, 72 and 94?__

lcm (21 72 94) = (?)

21 => 3 x 7

72 => 2 x 2 x 2 x 3 x 3

94 => 2 x 47

= 2 x 3 x 7 x 2 x 2 x 3 x 47

= 23688

lcm (21, 72 and 94) = 23688

23688 is the lcm of 21, 72 and 94.

__where,__

21 is a positive integer,

72 is a positive integer,

23688 is the lcm of 21, 72 and 94,

{2, 3} in {3 x 7, 2 x 2 x 2 x 3 x 3, 2 x 47} are the most repeated factors of 21, 72 and 94,

{7, 2, 2, 3, 47} in {3 x 7, 2 x 2 x 2 x 3 x 3, 2 x 47} are the the other remaining factors of 21, 72 and 94.

__Use in Mathematics: LCM of 21, 72 and 94__

The below are some of the mathematical applications where lcm of 21, 72 and 94 can be used:

- to find the least number which is exactly divisible by 21, 72 and 94.
- to find the common denominators for the fractions having 21, 72 and 94 as denominators in the unlike fractions addition or subtraction.

__Use in Real-world Problems: 21, 72 and 94 lcm__In the context of lcm real world problems, the lcm of 21, 72 and 94 helps to find the exact time when three similar and recurring 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 all the bells A, B and C toll together, if bell A tolls at 21 seconds, B tolls at 72 seconds and C tolls at 94 seconds repeatedly. The answer is that all bells A, B and C toll together at 23688 seconds for the first time, at 47376 seconds for the second time, at 71064 seconds for the third time and so on.

__Important Notes: 21, 72 and 94 lcm__The below are the important notes to be remembered while solving the lcm of 21, 72 and 94:

- The repeated and non-repeated prime factors of 21, 72 and 94 should be multiplied to find the least common multiple of 21, 72 and 94, when solving lcm by using prime factors method.
- The results of lcm of 21, 72 and 94 is identical even if we change the order of given numbers in the lcm calculation, it means the order of given numbers in the lcm calculation doesn't affect the results.

## How-to: What is the LCM of 21, 72 and 94?

__Solved example using prime factors method:__

What is the LCM of 21, 72 and 94?

step 1 Address the input parameters, values and observe what to be found:

__Input parameters and values:__

A = 21

B = 72

C = 94

__What to be found:__

find the lcm of 21, 72 and 94

step 2 Find the prime factors of 21, 72 and 94:

Prime factors of 21 = 3 x 7

Prime factors of 72 = 2 x 2 x 2 x 3 x 3

Prime factors of 94 = 2 x 47

step 3 Identify the repeated and non-repeated prime factors of 21, 72 and 94:

{2, 3} are the most repeated factors and {7, 2, 2, 3, 47} are the non-repeated factors of 21, 72 and 94.

step 4 Find the product of repeated and non-repeated prime factors of 21, 72 and 94:

= 2 x 3 x 7 x 2 x 2 x 3 x 47

= 23688

lcm(20 and 30) = 23688

Hence,

lcm of 21, 72 and 94 is 23688

__Solved example using special division method:__

This special division method is the easiest way to understand the entire calculation of what is the lcm of 21, 72 and 94.

step 1 Address the input parameters, values and observe what to be found:

__Input parameters and values:__

Integers: 21, 72 and 94

__What to be found:__

lcm (21, 72, 94) = ?

step 2 Arrange the given integers in the horizontal form with space or comma separated format:

21, 72 and 94

step 3 Choose the divisor which divides each or most of the given integers (21, 72 and 94), 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 21, 72 and 94 is not divisible by the selected divisor; repeat the same process until all the integers are brought to 1 as like below:

2 | 21 | 72 | 94 |

2 | 21 | 36 | 47 |

2 | 21 | 18 | 47 |

3 | 21 | 9 | 47 |

3 | 7 | 3 | 47 |

7 | 7 | 1 | 47 |

47 | 1 | 1 | 47 |

1 | 1 | 1 |

step 4 Multiply the divisors to find the lcm of 21, 72 and 94:

= 2 x 2 x 2 x 3 x 3 x 7 x 47

= 23688

LCM(21, 72, 94) = 23688

The least common multiple for three numbers 21, 72 and 94 is 23688