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?  Pick one
A) 20%
B) 30%
C) 40%
D) 70%
E) 80%
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= 
<gadget id="calculator">(0.7)*100</gadget>
<output>70</output>
70%.   70%
<result>D</result>
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?