Question

Steve invested money in the stock market. In the first year, his stock increased 50%. He paid his stockbroker $350 and then lost $400. He withdrew $300, and then his remaining investment doubled. Steve's investment is now worth $8100. How much was Steve's original investment?

Answer 1

Original amount invested = $3400 .

Explanation:

Let the original investment of Steve = $x

Stock increased in the first year = 50% of amount invested

Therefore total amount after one year = x + 0.5x = 1.5x

Commission paid to the stock broker = $350

Amount lost by him = $400

Amount withdrawn by him = $300

Total amount decreased from the amount after 1 year

= 1.5x - (350 + 400 + 300)

= 1.5x - 1050

This remaining amount is doubled, so the final amount

= 2(1.5x - 1050)

= 3x - 2100

This final amount is equal to $8100

3x - 2100 = 8100

3x = 8100 + 2100

3x = 10200

x = $3400

Therefore original amount invested in the stock market was $3400 .