Your developers provision many custom virtual machines each week and delete them within the same week. 60% run Windows Server 2016 and 40% run Ubuntu. You need to reduce administrative effort by using an appropriate Azure service. Solution: Recommend Azure Reserved Virtual Machine Instances. Does this meet the goal?

This solution does not meet the goal because Azure Reserved Virtual Machine Instances (RIs) are designed for long-term, predictable workloads (typically one or three years) to reduce costs. Since the virtual machines are provisioned and deleted within the same week, they are short-lived and temporary, making RIs unsuitable. RIs require a commitment period, and the benefit is realized over that duration. For short-lived VMs, services like Azure Spot Virtual Machines or Azure DevTest Labs might be more appropriate for cost savings and administrative efficiency, respectively, but RIs are not.