1. Membalik perbandingan

\(\dfrac ab = \dfrac 25\) → \(\dfrac ba = \dfrac 52\)

2. Membagi perbandingan

\(\dfrac ab = \dfrac 25\) → \(\dfrac a2 = \dfrac b5\)

3. Kali silang

\(\dfrac ab = \dfrac 25\) → \(5 \times a = 2 \times b\)