These math problems are reduced to descriptive questions, and you only need to enter numbers in the fields and they will be answered immediately.
Find a best time between two time zones. This is a free meeting planner tool to schedule the time for meeting, skype chat, webinars or calls. A very simple slider interface to schedule the time across time zones.
What time is it? Do you want to adjust time to your local time zone? You can adjust time by this tool without installing any software.
This tool was inspired from this article which describes facebook might defined good friends by using some algorithm.