Get data from another table for calculation

I've a table with timesheet data of employees. Let's call this Timesheet. This table has actual hours logged by the employees. There is another table called Holiday_Calendar which has the total working hours for each month.

Timesheet table has Log_Owner_Name, Log_Date, Log Hours.

Holiday_Calendar table has Year, Month, Total_Working_Hours

Now, I want to calculate the resource utilization based on the following formula:
Sum of Log Hours / (Total_Working_Hours * No. of log owner names)

How do I get the Available Hours for each month without joining the two tables?

If you want to perform calculations on data from two different tables you would need to link them together somehow. Perhaps I'm not understanding the context - is there a reason you want to avoid a join?