Question

A notebook costs Rs 9 while a pen costs Rs 15. Find the ratio of the cost of the pen to that of the notebook.

Answer 1

Cost of the notebook = Rs 9
Cost of the pen = Rs 15
∴ Ratio of the cost of pen to the cost of the notebook$=\frac{\mathrm{Cost}\mathrm{of}\mathrm{the}\mathrm{pen}}{\mathrm{Cost}\mathrm{of}\mathrm{the}\mathrm{notebook}}$

$$\begin{gathered} =\frac{15}{9} \\ =\frac{15÷3}{9÷3} \\ =\frac{5}{3} \\ =5:3 \end{gathered}$$