Question 252744
An instrument store gives a 10% discount to all students off the original cost of an instrument. 
During a back to school sale an additional 15% is taken off the discounted price. Julie, a student at the local high school, purchases a flute for $306.
 How much did it originally cost?
:
x = original cost
:
If she a has 10% discount, she is paying 90% of the original cost (.9x)
.9x - .15(.9x) = 306
.9x - .135x = 306
.765x = 306
x = {{{306/.765}}}
x = $400