Rule 1 — Sum/Difference (Z = A +/- B): Delta(Z) = Delta(A) + Delta(B) (absolute errors add)

Rule 2 — Product/Quotient (Z = A*B or Z = A/B): Delta(Z)/Z = Delta(A)/A + Delta(B)/B (relative errors add)

Rule 3 — Power (Z = A^n): Delta(Z)/Z = |n| * Delta(A)/A

Rule 4 — General (Z = A^p * B^q / C^r): Delta(Z)/Z = |p|*Delta(A)/A + |q|*Delta(B)/B + |r|*Delta(C)/C

Critical insight: The quantity raised to the highest power contributes the most to the error. If measuring density rho = M/(pir^2L), the error in r is doubled (power 2) and dominates.