By selling 50 meters of cloth. I gain the selling price of 20 meters. Find the gain percent? Choose the correct choice from the following choices:
A) 42 7/7%  B) 42 5/8%  C) 42 6/4%  D) 42 6/8%  E) 66 2/3%
SP = CP + g   50 SP = 50 CP + 20 SP   30 SP = 50 CP   30 --- 20 CP gain   100 --- ? =&gt; 66 2/3%   Answer: 66 2/3%
<result>E</result>
By selling 50 meters of cloth. I gain the selling price of 20 meters. Find the gain percent?