The sampling plan uses a ____ chart indicating the number of parts to inspect based on batch size.

The choice of using a frequency chart in a sampling plan is accurate because a frequency chart directly relates to determining how often and how many items need to be inspected based on the size of the batch. In quality control processes, it is essential to balance the need for quality assurance with the efficiency of the inspection process. A frequency chart allows practitioners to establish a systematic approach for sampling that takes into account the total number of items in the batch, ensuring that enough samples are inspected to make reliable judgments about quality without inspecting every single piece.

This reliance on a frequency chart is crucial since it provides a standardized method for determining inspection levels that can change with batch size, allowing for scalability and adaptability in various production scenarios. It is common in quality practices to establish these parameters to effectively gauge quality without incurring unnecessary costs or time through exhaustive inspection of all items. Tools like frequency charts are foundational in implementing statistical process control (SPC) and align with the principles of continuous improvement in quality management.