Dad drove to work, and the road was congested when he went. He traveled an average of 32 kilometers per hour and arrived at 0.5 o'clock. It only took 0.4 hours when I came back from get off work. How many kilometers per hour did Dad travel more than when he went?
爸爸开车去上班，去时路上交通拥堵，平均每小时行32千米，0.5时到达．下班回来时只用了0.4时，爸爸回来时比去时每小时多行多少千米？
<gadget id="calculator">0.5 / 0.4</gadget>
<output>1.25</output>

<gadget id="calculator">32 * 1.25</gadget>
<output>40</output>

<gadget id="calculator">40 - 32</gadget>
<output>8</output>

<result>8</result>