Math
LCM function: find shared maintenance intervals and common denominators
Calculate the smallest positive cycle where two or more repeating schedules align simultaneously using LCM.
Find when independent service intervals coincide
If Pump A is inspected every 12 days and Valve B every 18 days, LCM(12, 18) = 36 tells you both tasks fall on the exact same day every 36 days—letting maintenance teams bundle downtime.
Adding a third 15-day filter cycle gives LCM(12, 18, 15) = 180 days for a full three-system overhaul.
This assumes the cycles start from the same reference date and use the same time unit. Different phase offsets need an additional alignment calculation; the LCM alone does not determine the first shared date.
| PumpCycle (A) | ValveCycle (B) | FilterCycle (C) | Combined LCM |
|---|---|---|---|
| 12 | 18 | 15 | 180 days |
Compute two-task and three-task alignment intervals
LCM(A2, B2) returns 36 days for the first two components, while LCM(A2:C2) returns 180 days across all three.
=LCM(A2, B2)Zero cycle returns 0; guard negative inputs
If any argument is 0, LCM returns 0. Guard negative inputs with IF(MIN(A2:C2)<0, ...) so schedule errors stay visible.
=LCM(0, B2)Try the example
Use the original values or change them to test your understanding.