Xiaohong bought a bottle of soda. After drinking half of the soda, the weight of the bottle is 550 grams. How heavy?
小红买了一瓶汽水，当喝了汽水的一半后，连瓶共重550克；当喝了汽水的(9/10)后，连瓶共重350克，这瓶汽水(瓶子和汽水)有多重？
<gadget id="calculator">550 - 350</gadget>
<output>200</output>

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

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(9/10) - (1/2)</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">200 / (2/5)</gadget>
<output>500</output>

<result>500</result>