A car drives from place A to place B. It travels 50 kilometers in the first hour, and travels 20% of the distance in the second hour, leaving 190 kilometers left. How many kilometers are there between A and B?
一辆汽车从甲地驶向乙地，第一小时行了50千米，第二小时行了全程的20%，还剩下190千米．甲乙两地相距多少千米？
<gadget id="calculator">50 + 190</gadget>
<output>240</output>

<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">240 / (4/5)</gadget>
<output>300</output>

<result>300</result>