A bus carries a total of 50 passengers, some of whom get off halfway, and each ticket costs 0.6 yuan, and the other part gets off at the end, and each ticket costs 0.9 yuan. The conductor collected a total of 36.9 yuan. Q: How many people got off in the middle?
一辆公共汽车共载客50人，其中一部分人在中途下车，每张票价0.6元，另一部分到终点下车，每张票价0.9元．售票员共收票款36.9元．问：中途下了多少人？
<gadget id="calculator">50 * 0.9</gadget>
<output>45</output>

<gadget id="calculator">45 - 36.9</gadget>
<output>8.1</output>

<gadget id="calculator">0.9 - 0.6</gadget>
<output>0.3</output>

<gadget id="calculator">8.1 / 0.3</gadget>
<output>27</output>

<result>27</result>