1 .
In a supermarket , the marked price of a bottle of milk is $ 6 . If a customer buys 3 bottles , he can get an extra bottle for free . What is the discount per cent ?
2.
Jim paid $ 800 for a ticket to a concert at a student discount of 20 % .
a) What was the marked price of Jim's ticket ?
b) Kerry also bought a ticket to the concert with the same marked price and student discount . However , Kerry got an extra 10 % off the selling price because she belonged to a fan club . At what overall discount per cent did Kerry buy her ticket ?
更新1:
a) What was the marked price of Jim's ticket ?