From the beginning to the end of 2007, the price of a stock rose 20 percent. In 2008, it dropped 25 percent. In 2009, it rose 25 percent. What percent of the stockâ€™s 2007 starting price was the price of the stock at the end of 2009?  Select the correct option.
A) 80
B) 90
C) 95
D) 100
E) 112.5
Assume a value at the beginning of 2007. As this is a % question, assume P=100.   At the end of 2007 it becmae = 1.2*100= 
<gadget id="calculator">1.2*100</gadget>
<output>120</output>
120   At the end of 2008 it decreased by 25%= 120*.75= 
<gadget id="calculator">120*.75</gadget>
<output>90</output>
90   At the end of 2009 it increased by 25%= 90*1.25= 
<gadget id="calculator">90*1.25</gadget>
<output>112.5</output>
112.5   Thus ratio= 112.5/100= 
<gadget id="calculator">112.5/100</gadget>
<output>1.125</output>
1.125 (in % terms= 12.5%). Thus 112.5 is the correct answer.
<result>E</result>
From the beginning to the end of 2007, the price of a stock rose 20 percent. In 2008, it dropped 25 percent. In 2009, it rose 25 percent. What percent of the stockâ€™s 2007 starting price was the price of the stock at the end of 2009?