A passenger carries 30 kilograms of luggage by plane. According to civil aviation regulations, passengers can carry up to 20 kilograms of luggage free of charge. The overweight part is purchased at 1.5% of the plane ticket price for each kilogram; How much should the price be.
一旅客携带了30千克行李乘飞机，按民航规定，旅客最多可免费携带20千克行李，超重部分每千克按飞机票价的1.5%购买行李；该旅客购买了120元行李，则它的飞机票价应是多少元．
<gadget id="calculator">30 - 20</gadget>
<output>10</output>

<gadget id="calculator">1.5 / 100</gadget>
<output>0.015</output>

<gadget id="calculator">120 / 10 / 0.015</gadget>
<output>800</output>

<result>800</result>