The passenger car and the truck depart from A and B cities, which are 320 kilometers apart, and head toward each other. The truck travels 36 kilometers per hour. After 1.5 hours, the bus departs from City A and meets the truck after another 3.5 hours. How many kilometers does the bus travel per hour? (solution by equation)
客车和货车从相距320千米的甲、乙两城出发，相向而行，货车每小时行36千米，1.5小时后客车才从甲城出发，又经3.5小时与货车相遇．客车每小时行多少千米？(用方程解)
<gadget id="calculator">36 * 3.5</gadget>
<output>126</output>

<gadget id="calculator">36 * 1.5</gadget>
<output>54</output>

<gadget id="calculator">320 - 126 - 54</gadget>
<output>140</output>

<gadget id="calculator">140 / 3.5</gadget>
<output>40</output>

<result>40</result>