Zhang Lan, Zheng Huan and Xie Ling shared a taxi. The starting fare was 8 yuan for 3 kilometers, and 2.4 yuan per kilometer for the excess. They traveled a total of 8 kilometers to the Science and Technology Exhibition Hall. How much should they pay for the fare?
张兰、郑欢和谢玲三人合坐一辆出租车，起步价3千米8元，超过部分按每千米2.4元计算．他们到科技展览馆一共8千米，应付车费多少元？
<gadget id="calculator">8 - 3</gadget>
<output>5</output>

<gadget id="calculator">2.4 * 5</gadget>
<output>12</output>

<gadget id="calculator">12 + 8</gadget>
<output>20</output>

<result>20</result>