A computer-based operations management system that uses sales forecasts to make sure that needed parts and materials are available at the right time and place is referred to as requirement plannin

The system you're referring to is known as Material Requirements Planning (MRP). Here's a step-by-step explanation of how it works:

1. Sales Forecasting: The process begins with a forecast of sales to estimate the quantity of each product that will be sold.

2. Bill of Materials: This is a list of all the materials and components needed to produce each product. It includes the quantity of each item required.

3. Inventory Records: These records provide information about the quantity of materials and components currently in stock.

4. Material Requirements Plan: Using the sales forecast, the bill of materials, and the inventory records, the MRP system calculates the quantity of each material or component that needs to be purchased or produced, and the timing of these actions.

5. Purchase Orders and Work Orders: Based on the material requirements plan, the MRP system generates purchase orders for materials that need to be bought from suppliers, and work orders for components that need to be produced in-house.

6. Adjustments: The MRP system continually updates the material requirements plan based on actual sales, changes in the sales forecast, and changes in inventory levels.

So, in summary, a Material Requirements Planning (MRP) system is a computer-based operations management system that uses sales forecasts to ensure that the necessary parts and materials are available when and where they are needed.