A person rides a bicycle from A to B at a speed of 8 kilometers per hour. When returning, he detours and walks an extra 3 kilometers. Although the speed increases to 9 kilometers per hour, the time spent is still 7.5 times longer than before. Minutes, how many kilometers did the person travel round and back?
某人骑自行车以每小时8千米的速度从甲地到乙地，回来时绕道而行多走了3千米，虽然速度增加到每小时9千米，所用时间仍比去时多用了7.5分钟，问此人往返路程共多少千米？
<gadget id="calculator">7.5 / 60</gadget>
<output>0.125</output>

<gadget id="calculator">9 * 0.125</gadget>
<output>1.125</output>

<gadget id="calculator">3 - 1.125</gadget>
<output>1.875</output>

<gadget id="calculator">9 - 8</gadget>
<output>1</output>

<gadget id="calculator">1.875 / 1</gadget>
<output>1.875</output>

<gadget id="calculator">1.875 * 8</gadget>
<output>15</output>

<gadget id="calculator">15 + 3 + 15</gadget>
<output>33</output>

<result>33</result>