> How do you find capital gain?

How do you find capital gain?

Posted at: 2014-12-05 
$6340 gain against $3100 investment, which is about 200% gain

Nikola bought shares of a brand new corporation that manufacturers dish antennas. He bought the stock years ago for $3,100. He recently sold this stock for 9,440. Express his capital gain as a percent of the original total purchase price. Round to the nearest tenth of a percent.