How is the "Available to Transact" quantity calculated on the Item Availability page?

According to the Mock Exams: Oracle SCM Business Process Foundation Associate document3, available to transact quantity is calculated on the Item Availability page as follows:

Available to Transact = (Quantity On Hand) - Pending Transactions - Reservations

Quantity On Hand is the amount of inventory that is physically present in a location or organization. Pending Transactions are the transactions that have not been completed or posted yet, such as receipts, issues, transfers, etc. Reservations are the allocations of inventory to specific demands, such as sales orders, work orders, transfer orders, etc.