an instrument store gives 10% discount to all students off the original cost of instrument. during back to school sale on

Question

an instrument store gives 10% discount to all students off the original cost of instrument. during back to school sale on additional 15% is taken off the discounted price. Julie a student at the local high school purchase a flute for $306 how much did it originally cost?

Answer 1

Let 'x' be the original price of the flute. As a student she would get it for $x*(1-1/10). During back to school she got additional discount of 15%. So she paid $x*0.9*(1-15/100. That is she paid $x*0.765. The actual amount she paid was $306 therefore the original price must be 306/0.765 that is $400.