Note 5 — PROPORTION.
Reading edition
In this case cross dividing gives a constant quotient, e.g., 8 ÷ 3 = 4 ÷ 1·5. Since the upper scale is now a scale of reciprocals, the ratio is really
O ⅛ ¼
D 1·5 3
Reading edition
In this case cross dividing gives a constant quotient, e.g., 8 ÷ 3 = 4 ÷ 1·5. Since the upper scale is now a scale of reciprocals, the ratio is really
O ⅛ ¼
D 1·5 3