Calculating Margin Requirements

Suppose you buy a round lot of 100 shares of XYX stock on a 55% margin. The stock is currently being sold at a$20 per share. Lets assume the broker fee is 10% (per annum), and commission is 3% of stock value on purchase and sale price. Two years after, XTX send you dividends at a rate of $0.50 per share and you sell the stock at $27/share. Calculate the rate of return on this stock.