Jeanette purchased a concert ticket on a web site. The original price of the ticket was $75. She used a coupon code to receive a 20% discount. The web site applied a 10% service fee to the discounted price. Jeanette’s ticket was less than the original price by what percent?

The problem says that the original price of the ticket was $75 and Jeanette used a coupon code to receive a 20% discount. So, you have:
 
 20%=20/100=0.20
 75$x.0.20=15$
 
 The price when she received a 20% discount was:
 
 75$-15$=60$
 
 Then, the web site applied a 10% service fee to the discounted price, so you have:
 
 10/100=0.10
 75$x0.10=7.5$
 60$+7.5$=67.5$
 
 So, if 75$ is the 100% of the price, what percentage represents 67.5$?
 
 75$--------100%
 67.5$------x
 
 x=67.5x100/75
 x=90%
 
 Then, you obtain:
 
 100%-90%=10%
 
 Jeanette’s ticket was less than the original price by what percent?
 
 The answer is: 10%