Answer:
14%
Explanation:
You want to know the rate of return on 40 shares of stock bought at $15 each and sold at $690, with a commission on the sale of $6.
Return
The proceeds from the sale were ...
selling price - commission = $690 -6 = $684
The amount of return is the difference from the purchase price:
$684 -40($15) = $685 -600 = $84
Percent return
The return expressed as a percent of the investment is ...
(84/600)×100% = 14%
The rate of return on the stock was 14%.