If p : q = 3 : 4, r : s = 8 : 5 and x : y = 10 : 6, then psx : qry is equal to.

Answer: Option B

$$\begin{array}{rl}& =\frac{p}{q}=\frac{3}{4},\frac{r}{s}=\frac{8}{5},\frac{x}{y}=\frac{10}{6}\\ & \Rightarrow p=\frac{3q}{4},r=\frac{8s}{5},x=\frac{5y}{3}\\ & \therefore \frac{psx}{qry}=\frac{\frac{3q}{4}\times s\times \frac{5y}{3}}{q\times \frac{8s}{5}\times y}\\ & =\frac{\frac{5}{4}qsy}{\frac{8}{5}qsy}\\ & =\frac{5}{4}\times \frac{5}{8}\\ & =\frac{25}{32}\end{array}$$