Reciprocal ratio of a:b is:
Aa²:b²
Ba:b
Cb:a
D1/a : 1/b only
Answer & Solution
Correct answer: C. b:a
1. Per OCR header: "Inverse ratio or reciprocal ratio:" — reciprocal of a:b is b:a.
2. Equivalent to applying Invertendo.
3. Useful when relating speed-time-distance ratios.
_Source: ICMAI BoS CMA Foundation Paper 3 (FBMS) — Paper3_07042026.pdf, Module 1 §1.1 (page 11)_