A man sells two chairs at Rs. 120 each and by doing so he gains 25% on one chair and loses 25% on the other. His loss on the whole in Rs. is = ?

$$\eqalign{ & {\text{C}}{\text{.P}}{\text{.}}\,{\text{of first chair}} \cr & = \frac{{100}}{{125}} \times 120 = {\text{Rs}}{\text{.}}\,96 \cr & {\text{C}}{\text{.P}}{\text{.}}\,\,{\text{of}}\,{\text{second}}\,{\text{chair}} \cr & = \frac{{100}}{{75}} \times 120 = {\text{Rs}}{\text{.}}\,160 \cr & \therefore {\text{Loss}} = 160 + 96 - 240 \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = {\text{Rs}}{\text{.}}\,16 \cr} $$