Buy a batch of goods with 1,000 yuan, sell them the next day, and make a profit of 10%; a few days later, he buys a batch of the same goods at 90% of the last selling price. All of them are sold at 10% off the second purchase price. How did he profit and lose on these two transactions?
用1000元人民币购进一批货物，第二天出售，获利10%；过几天后又以上次售出价的90%购进一批同样的货，由于卖不出去，两天后他将其按第二次购进价的九折全部卖出．他在这两次交易中盈亏如何？
<gadget id="calculator">10 / 100</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">1_000 * (1/10)</gadget>
<output>100</output>

<gadget id="calculator">1_000 + 100</gadget>
<output>1_100</output>

<gadget id="calculator">90 / 100</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">1_100 * (9/10)</gadget>
<output>990</output>

<gadget id="calculator">1 - (9/10)</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">990 * (1/10)</gadget>
<output>99</output>

<gadget id="calculator">100 - 99</gadget>
<output>1</output>

<result>1</result>