A small-displacement car consumes 6 liters of fuel per 100 kilometers, and another large-displacement car consumes 9 liters per 100 kilometers. It takes about 90 kilometers to travel from Xuchang to Zhengzhou. How many liters of fuel can a small-displacement car save compared to a large-displacement car?
一款小排量轿车每行驶100千米耗油6升，另一款大排量轿车每行驶100千米耗油9升．从许昌到郑州大约要行90千米，小排量轿车比大排量轿车可节省燃油多少升？
<gadget id="calculator">9 / 100</gadget>
<output>9/100 = around 0.09</output>

<gadget id="calculator">6 / 100</gadget>
<output>3/50 = around 0.06</output>

<gadget id="calculator">(9/100) - (3/50)</gadget>
<output>3/100 = around 0.03</output>

<gadget id="calculator">(3/100) * 90</gadget>
<output>27/10 = around 2.7</output>

<result>27/10 = around 2.7</result>