bottle of soy sauce, after using a part, there is still (1/2) liter left, and there is still (1/5) left, how many liters is this bottle of soy sauce originally?
一瓶酱油，用去一部分后还剩(1/2)升，还剩(1/5)，这瓶酱油原来有多少升？
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(1/2) / (1/5)</gadget>
<output>5/2 = around 2.5</output>

<result>5/2 = around 2.5</result>