train travels from city A to city B. If it travels at a speed of 24 kilometers per hour, it will arrive at City B at 1 pm; if it travels at a speed of 40 kilometers per hour, it will arrive at City B at 11 am. To make the train arrive at City B at 12:00 noon, what speed should the train travel at?
一列火车从甲城开往乙城．如果以每小时24千米的速度行驶，它将于下午1时到达乙城；如果以每小时40千米的速度行驶，它将于上午11时到达乙城．要使这列火车于中午12时到达乙城，那么这列火车应以怎样的速度行驶？
<gadget id="calculator">24 + 40</gadget>
<output>64</output>

<gadget id="calculator">40 - 24</gadget>
<output>16</output>

<gadget id="calculator">64 / 16</gadget>
<output>4</output>

<gadget id="calculator">5 / 4</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">24 * (5/4)</gadget>
<output>30</output>

<result>30</result>