A bus is driving from Zhenjiang to a certain place. There are still 3 empty seats on the bus. When it stops for the first time on the way, (1/5) of the passengers get off and 12 people get on the bus. At this time, the seats in the car were full. How many passenger seats does this bus have?
一辆大客车从镇江开往某地，出发时车上还有3个空座位，中途第一次停站时，车上有(1/5)的乘客下车，又有12人上车，这时车上座位正好坐满．这辆大客车一共有多少个乘客座位．
<gadget id="calculator">12 - 3</gadget>
<output>9</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">9 / (1/5)</gadget>
<output>45</output>

<gadget id="calculator">45 + 3</gadget>
<output>48</output>

<result>48</result>