Wang Hua walks 3.2 kilometers per hour from home to school and arrives in 0.8 hours. If he walks 4 kilometers per hour, how long will it take to get there?
王华从家到学校，每小时走3.2千米，0.8小时到达，如果每小时走4千米，要走多长时间到达？
<gadget id="calculator">0.8 / 4</gadget>
<output>0.2</output>

<gadget id="calculator">3.2 * 0.2</gadget>
<output>0.64</output>

<result>0.64</result>