3.3.3.2a - Simple payback

Calculate and interpret simple payback.

Use a - simple payback to connect the rule to the data and decision in the question.

This matters because a - simple payback determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply a - simple payback to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: a - Simple payback is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.