The ship travels from Port A to Port B for 3 days. On the first day, it travels the whole distance (2/5), on the second day it travels the whole distance (1/3), on the third day it travels 280km, from Port A to B How many kilometers is the voyage of the port?
轮船从甲港开往乙港共行3天，第一天行了全程的(2/5)，第二天行了全程的(1/3)，第三天行了280km，甲港到乙港的航程有多少km？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 - (2/5) - (1/3)</gadget>
<output>4/15 = around 0.266667</output>

<gadget id="calculator">280 / (4/15)</gadget>
<output>1_050</output>

<result>1_050</result>