$\begin{array}{1 1} \text {When x=5,y=2.5 and when y=5,x=10, then x and y are inversely proportional } \\ \text {When x=10,y=5 and when x=20,y=2.5 then xy = constant } \\ \text{If x and y vary inversely, then on decreasing x,y will decrease in proportion} \\ \text{If x and y vary directly then on x,y will increase in proportion } \end{array} $
