John want to buy a $100 Trouser at the store, but he think it’s too expensive. Finally, it goes on sale for $20. What is the percent decrease? Choose the correct choice from the following options.
A) 20 %
B) 30 %
C) 40 %
D) 70 %
E) 80 %

Rationale: "the is always the difference between our starting and ending points . in this case , it ’ s 100 – 20 = 80 . the “ original ” is our starting point ; in this case , it ’ s 100 . ( 80 / 100 ) * 100 = ( 0.8 ) * 100 = 80 % . e"
Answer: E