The NASDAQ index has decreased by 70% since year 2000. How much should the index increase in order to gain the same value as in year 2000 ?
Choose the correct answer:
A) 400%  B) 80%  C) 233%  D) 60%  E) None of the above
Let x be the index in the year 2000. After the decrease it becomes 0.3x   Now for 0.3x to reach 1x it has to raise by 0.7x. The increase needs to be 0.7x/0.3x*100=233.3%   Answer 233%
<result>C</result>
The NASDAQ index has decreased by 70% since year 2000. How much should the index increase in order to gain the same value as in year 2000 ?