Respuesta :
Given:
The original price, CP=$65.
The initial discount on sale, D1=10%.
The additional discount, D2=15%.
If the cost price(CP) of an item is given, then the selling price after the first discount is applied is,
[tex]SP=CP\times(\frac{1-First\text{ }Discount\text{ Percentage}}{100})[/tex]The additional discount is applied to the price after the first discount is applied. So, the final price after applying the second discount is,
[tex]SP^{\prime}=SP\times(\frac{1-Second\text{ }Discount\text{ Percentage}}{100})[/tex]Applying the first discount on the original price, the selling price is,
[tex]\begin{gathered} SP=CP\times\frac{(100-D1)}{100} \\ =65\times\frac{(100-10)}{100} \\ =58.5 \end{gathered}[/tex]Applying the second discount on the selling price, the final selling price is,
[tex]\begin{gathered} SP^{\prime}=SP_{}\times\frac{(100-D2_{})}{100} \\ =58.5_{}\times\frac{(100-15_{})}{100} \\ \cong49.73 \end{gathered}[/tex]Therefore, the final price is $49.73.
Note:
The direct formula for the final price if two successive discounts D1 and D2 are applied to a cost price CP is,
[tex]SP=CP\times(\frac{100-D1}{100})(\frac{100-D2}{100})[/tex]