The distance between A and B is 45 kilometers. Zhang and Wang start from A to B at the same time. Zhang travels 15 kilometers per hour on a bicycle, and Wang travels 6 kilometers per hour. Zhang stays for 1 hour after arriving at B. , met the king on the way back to A, how many kilometers away were they from B when they met?
甲、乙两地相距45千米，张、王两人同时从甲地出发去乙地，张骑自行车每小时行15千米，王每小时行6千米，张到达乙地后停留1小时，返回甲地途中与王相遇，相遇时他们距乙地多少千米？
<gadget id="calculator">45 / 15</gadget>
<output>3</output>

<gadget id="calculator">3 + 1</gadget>
<output>4</output>

<gadget id="calculator">6 * 4</gadget>
<output>24</output>

<gadget id="calculator">45 - 24</gadget>
<output>21</output>

<gadget id="calculator">15 + 6</gadget>
<output>21</output>

<gadget id="calculator">21 / 21</gadget>
<output>1</output>

<gadget id="calculator">1 * 15</gadget>
<output>15</output>

<result>15</result>