A bus carries a total of 50 passengers, some of whom get off halfway, and each ticket costs 2 yuan, and the other part gets off at the end, each ticket costs 3 yuan, and the conductor collects a total of 127 yuan. How many people got off in the middle.
一辆公共汽车载客共50人，其中一部分在中途下车，每张票价2元，另一部分在终点下车，每张票价3元，售票员共收款127元．中途下了多少人．
<gadget id="calculator">50 * 3</gadget>
<output>150</output>

<gadget id="calculator">150 - 127</gadget>
<output>23</output>

<gadget id="calculator">3 - 2</gadget>
<output>1</output>

<gadget id="calculator">23 / 1</gadget>
<output>23</output>

<result>23</result>