C.1.5—Combined measurement uncertainty

Identify measurement uncertainties and determine uncertainty when data are combined by addition, subtraction, multiplication, division or powers.

Use c.1.5—combined measurement uncertainty to connect the rule to the data and decision in the question.

This matters because c.1.5—combined measurement uncertainty determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply c.1.5—combined measurement uncertainty to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: C.1.5—Combined measurement uncertainty is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.