It takes Mr. Wang 0.25 hours to ride a bicycle from home to school at a speed of 15 kilometers per hour. If he instead walks and walks 5 kilometers per hour, how many hours will it take to get to school?
王老师从家骑车到学校，以每小时15千米的速度要用0.25小时，如果改为步行，每小时走5千米，要用多少小时走到学校？
<gadget id="calculator">0.25 / 5</gadget>
<output>0.05</output>

<gadget id="calculator">15 * 0.05</gadget>
<output>0.75</output>

<result>0.75</result>