Question: how much money do you make when stocks go up?
Answer: If a stock goes up 100 percent, it's doubled in value. That's also reflected in the relative increase in your two investments. Your 200 shares of the first stock each increased by $5, giving you a 200 * $5 = $1,000 gain, while your 100 shares of the second stock each increased by $8, giving you a 100 * $8 = $800 gain.