A small-displacement car consumes 6 liters of fuel per 100 kilometers, and another large-displacement car consumes 10 liters of fuel per 100 kilometers. The two cars travel the same distance of 30 kilometers. The small-displacement car saves more than the large-displacement car. How many liters of fuel.
一辆小排量轿车每百公里耗油6升，另一辆大排量轿车每百公里耗油10升，两辆轿车同样行驶30千米的路程，小排量轿车比大排量轿车节省燃油多少升．
<gadget id="calculator">0.3 * 10</gadget>
<output>3</output>

<gadget id="calculator">0.3 * 6</gadget>
<output>1.8</output>

<gadget id="calculator">3 - 1.8</gadget>
<output>1.2</output>

<result>1.2</result>