A car drives from place A to place B and travels 40 kilometers per hour. After 4.5 hours, the ratio of the distance traveled to the distance not traveled is 3:7. How long will it take to reach place B?
一辆汽车从甲地开往乙地，每小时行40千米，4.5小时后，已行的路程和未行的路程比是3：7，还需要几个时才能到达乙地？
<gadget id="calculator">40 * 4.5</gadget>
<output>180</output>

<gadget id="calculator">180 / 3</gadget>
<output>60</output>

<gadget id="calculator">7 / 40</gadget>
<output>7/40 = around 0.175</output>

<gadget id="calculator">60 * (7/40)</gadget>
<output>21/2 = around 10.5</output>

<result>21/2 = around 10.5</result>