**LCM Function in Microsoft Excel**

### Part 1: Introduce

**Definition:**

The LCM function in Microsoft Excel returns the least common multiple of integers.

**Purpose:**

The primary purpose of the LCM function is to determine the smallest positive integer, which is a multiple of all the provided integer arguments. It’s beneficial when adding fractions with different denominators.

**Syntax & Arguments:**

`LCM(number1, [number2], ...)`

**Explain the Arguments in the function:**

**number1, number2,…:**Number1 is mandatory, while subsequent numbers are optional. You can provide between 1 to 255 values for which you want the least common multiple. If a value is not an integer, it will be truncated.

**Return value:**

The function returns the least common multiple of the provided integers.

**Remarks:**

- If any argument is nonnumeric, LCM returns the #VALUE! Error value.
- If any argument is less than zero, LCM returns the #NUM! Error value.
- If the result of LCM(a,b) is greater than or equal to 2^53, LCM returns the #NUM! Error value.

### Part 2: Examples

**Example 1:**

**Purpose of illustration:**Find the least common multiple of 5 and 2.**Data sheet and formulas:**

A | B | C | D | |
---|---|---|---|---|

1 | Data1 | Data2 | Formula | Result |

2 | 5 | 2 | `=LCM(A2, B2)` | 10 |

**Explanation:**The least common multiple of 5 and 2 is 10.

**Example 2:**

**Purpose of illustration:**Find the least common multiple of 24 and 36.**Data sheet and formulas:**

A | B | C | D | |
---|---|---|---|---|

1 | Data1 | Data2 | Formula | Result |

2 | 24 | 36 | `=LCM(A2, B2)` | 72 |

**Explanation:**The least common multiple of 24 and 36 is 72.

**Example 3:**

**Purpose of illustration:**To find the least common multiple of three numbers.**Data sheet and formulas:**

A | B | C | D | E | |
---|---|---|---|---|---|

1 | Data1 | Data2 | Data3 | Formula | Result |

2 | 3 | 4 | 5 | `=LCM(A2, B2, C2)` | 60 |

**Explanation:**The least common multiple of 3, 4, and 5 is 60.

**Example 4:**

**Purpose of example:**To find the least common multiple of two numbers, one of which is a decimal.**Data sheet and formulas:**

A | B | C | D | |
---|---|---|---|---|

1 | Data1 | Data2 | Formula | Result |

2 | 7.5 | 3 | `=LCM(A2, B2)` | 21 |

**Explanation:**The decimal 7.5 is truncated to 7. The least common multiple of 7 and 3 is 21.

**Example 5:**

**Purpose of illustration:**To demonstrate the error when using a negative number.**Data sheet and formulas:**

A | B | C | D | |
---|---|---|---|---|

1 | Data1 | Data2 | Formula | Result |

2 | -5 | 10 | `=LCM(A2, B2)` | #NUM! |

**Explanation:**Since one of the numbers is negative, the LCM function returns the #NUM! Error value.

**Example 6: Using LCM with IF Function**

**Purpose of example:**Find the LCM of two numbers if both are greater than 5; otherwise, return “Too Small”.**Data sheet and formulas:**

A | B | C | D | E | |
---|---|---|---|---|---|

1 | Data1 | Data2 | Formula | Result | Message |

2 | 6 | 8 | `=IF(AND(A2>5, B2>5), LCM(A2, B2), "Too Small")` | 24 |

**Explanation:**Since 6 and 8 are more significant than 5, the LCM of 6 and 8 is calculated as 24.

**Example 7: Using LCM with SUM Function**

**Purpose of example:**To find the LCM of the sum of three numbers with another number.**Data sheet and formulas:**

A | B | C | D | E | F | |
---|---|---|---|---|---|---|

1 | Data1 | Data2 | Data3 | Data4 | Formula | Result |

2 | 3 | 4 | 5 | 6 | `=LCM(SUM(A2:C2), D2)` | 78 |

**Explanation:**The sum of 3, 4, and 5 is 12. The LCM of 12 and 6 is 78.

**Example 8: Using LCM with VLOOKUP Function**

**Purpose of example:**To find the LCM of a value retrieved using VLOOKUP with another number.**Data sheet and formulas:**

A | B | C | D | E | |
---|---|---|---|---|---|

1 | Key | Value | Data4 | Formula | Result |

2 | 1 | 12 | 8 | `=LCM(VLOOKUP(1, A2:B2, 2, FALSE), C2)` | 24 |

**Explanation:**The VLOOKUP function retrieves the value 12 for the key 1. The LCM of 12 and 8 is 24.

**Example 9: Using LCM with AVERAGE Function**

**Purpose of example:**Find the LCM of the average of three numbers with another number.**Data sheet and formulas:**

A | B | C | D | E | F | |
---|---|---|---|---|---|---|

1 | Data1 | Data2 | Data3 | Data4 | Formula | Result |

2 | 6 | 12 | 18 | 3 | `=LCM(AVERAGE(A2:C2), D2)` | 9 |

**Explanation:**The average of 6, 12, and 18 is 12. The LCM of 12 and 3 is 9.

**Example 10: Using LCM with MAX Function**

**Purpose of example:**Find the LCM of the maximum value among three numbers with another number.**Data sheet and formulas:**

A | B | C | D | E | F | |
---|---|---|---|---|---|---|

1 | Data1 | Data2 | Data3 | Data4 | Formula | Result |

2 | 5 | 10 | 15 | 4 | `=LCM(MAX(A2:C2), D2)` | 60 |

**Explanation:**The maximum value among 5, 10, and 15 is 15. The LCM of 15 and 4 is 60.

**Example 11: Using LCM with MIN Function**

**Purpose of example:**Find the LCM of the minimum value among three numbers with another number.**Data sheet and formulas:**

A | B | C | D | E | F | |
---|---|---|---|---|---|---|

1 | Data1 | Data2 | Data3 | Data4 | Formula | Result |

2 | 9 | 18 | 27 | 6 | `=LCM(MIN(A2:C2), D2)` | 18 |

**Explanation:**The minimum value among 9, 18, and 27 is 9. The LCM of 9 and 6 is 18.

**Example 12: Using LCM with CONCATENATE Function**

**Purpose of illustration:**To concatenate a string with the LCM of two numbers.**Data sheet and formulas:**

A | B | C | D | |
---|---|---|---|---|

1 | Data1 | Data2 | Formula | Result |

2 | 7 | 14 | `=CONCATENATE("LCM Value: ", LCM(A2, B2))` | LCM Value: 14 |

**Explanation:**The LCM of 7 and 14 is 14. The CONCATENATE function then combines this value with the “LCM Value: “string, resulting in the final text “LCM Value: 14”.

### Part 3: Tips and tricks

- The LCM function is especially useful in scenarios involving fractions, as it helps find a common denominator.
- Always ensure the numbers provided as arguments are positive to avoid the #NUM! Error.
- If you’re unsure about the nature of your data, consider using conditional functions to check for negative values before applying the LCM function.
- Remember that non-integer values will be truncated, so it’s an excellent practice to round or format your data accordingly before using the LCM function.