Mr. Li walks at a speed of 4.5 km/h, how many meters per second does he walk on average?
李老师步行的速度是4.5千米/时，他平均每秒行多少米？
<gadget id="calculator">1 * 3_600</gadget>
<output>3_600</output>

<gadget id="calculator">1_000 / 3_600</gadget>
<output>5/18 = around 0.277778</output>

<gadget id="calculator">4.5 * (5/18)</gadget>
<output>1.25</output>

<result>1.25</result>