Mingming and three classmates went to the park to play. They bought the tickets with 50 yuan and left 18.8 yuan. How much is each ticket?
明明和3名同学到公园游玩．他们带50元钱买完门票还剩18.8元．门票每张多少钱？
<gadget id="calculator">50 - 18.8</gadget>
<output>31.2</output>

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

<gadget id="calculator">31.2 / 4</gadget>
<output>7.8</output>

<result>7.8</result>