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?

Question

i know its absurdly simple but my brain feels like mush right now

Answer 1

Do it step wise as the reverse of the original purchase.

So to get back to the discounted price (after the 10%) then multiply the £306 by 1/0.85. Then to get to the original price multiply this result by 1/0.9.

Answer 2

100%-15%= 85% 306/85%= 360
100%-10%= 90% 360/90%= 400

Hope this helps