John want to buy a $100 Trouser at the store, but he think it’s too expensive. Finally, it goes on sale for $30. What is the percent decrease? Choose the correct choice
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 – 30 = 70 . the “ original ” is our starting point ; in this case , it ’ s 100 . ( 70 / 100 ) * 100 = ( 0.7 ) * 100 = 70 % . d"
Answer: D