So how could you turn $300 into $1,500?
The below example explains how this can be achieved:

Day 1 Monday
You invested $300 on an Dow Jones option with a return rate of 70%. saying the Dow price will go up. It happened. The return was $513.
Day 2 Tuesday
You invested $513 on Oil option predicting the rate will go down in the next hour. The option return rate was 70%. The prediction was correct so you receive a return of $877.
Day 3 Wednesday
You bought with your $877 Gold option with a return rate of 70%. You predicted that in the next hour the price will go up and you succeeded! So you receive a return of $1,500.

So, the total return received would have been $1,500, with a profit of $1,200!