From A to B, Xiao Ming walked 5 kilometers per hour when he went, and 7 kilometers per hour when he came back. It took 24 hours to go back and forth. How many hours did it take Xiao Ming to go?
小明从甲地到乙地，去时每小时走5千米，回来时每小时走7千米，来回共用24小时，小明去时用了多少小时．
<gadget id="calculator">7 * 24</gadget>
<output>168</output>

<gadget id="calculator">5 + 7</gadget>
<output>12</output>

<gadget id="calculator">168 / 12</gadget>
<output>14</output>

<result>14</result>