In the case of positive independent variables, proceed as follows. The diagram shows a separable bivariate distribution formula_18 which has support in the positive quadrant formula_19 and we wish to find the pdf of the ratio formula_20. The hatched volume above the line formula_21 represents the cumulative distribution of the function formula_22 multiplied with the logical function formula_23. The density is first integrated in horizontal strips; the horizontal strip at height "y" extends from "x" = 0 to "x = Ry" and has incremental probability formula_24.<br>