Shopkeeper Discount and Profit

Cost price of 13 chairs $= 13 \times 100 = \text{Rs } 1300$. Overall profit desired is 26%, so total revenue collected from customer $= 1300 \times 1.26 = \text{Rs } 1638$. This revenue is received by charging the customer for 12 chairs at the discounted price per chair. Discounted price per chair $= MP \times (1 - 0.22) = 0.78 \times MP$. Total revenue $= 12 \times 0.78 \times MP = 9.36 \times MP$. $9.36 \times MP = 1638 \implies MP = \frac{1638}{9.36} = 175$ Thus, the marked price of each chair is Rs 175.