If the marked price of a laptop is $15\%$ more than its cost price and the shopkeeper offers a discount of $10\%$ on the marked price of the laptop, then find the profit percentage of the laptop.

Let the cost price ($\text{CP}$) of the laptop be \ 100$.Themarkedprice($ \text{MP}$)is$ 15\%$morethan$ \text{CP}$:$\text{MP} = 100 + \left(\frac{15}{100} \times 100\right) = \ 115
The shopkeeper offers a $10\%$ discount on $\text{MP}$:
\text{Discount} = \frac{10}{100} \times 115 = \$11.5$$Thesellingprice($ \text{SP}$)becomes:$\text{SP} = \text{MP} - \text{Discount} = 115 - 11.5 = \ 103.5
$$Profitpercentageiscalculatedas:$$
\text{Profit } \% = \frac{\text{SP} - \text{CP}}{\text{CP}} \times 100 = \frac{103.5 - 100}{100} \times 100 = 3.5\%
$$