A stock investment went up $25\%$ in 2006. Starting at this increased value, what percent would it have to go down in 2007 to be back to its original price at the beginning of 2006?
+36916 Say 'x' is the value before it goes up
it goes up 25 % then it equals 1.25 x
then it goes down to the original value of x
1.25 x - (%1.25 x) = x divide through by x
1.25 - %1.25 = 1
1 - % = 1 / 1.25
% = .2 20 percent
