On Saturday, 4 students went to visit the zoo, each ticket was 15 yuan, and the car shared 20 yuan. How much did each person spend on average?
星期六，4名同学去参观动物园，每张门票15元，坐车共用了20元．平均每人花了多少元．
<gadget id="calculator">20 / 4</gadget>
<output>5</output>

<gadget id="calculator">5 + 15</gadget>
<output>20</output>

<result>20</result>