For the same distance, a car travels in 3 hours and a bus in 4 hours. The speed of the bus is much slower than that of the car.
相同一段路程，轿车3小时行完，客车4小时行完，客车速度比轿车速度慢多少．
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(1/3) - (1/4)</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">(1/12) / (1/3)</gadget>
<output>1/4 = around 0.25</output>

<result>1/4 = around 0.25</result>