From point A to point B, it takes 10 hours for car A and 8 hours for car B. Now, cars A and B are traveling towards each other at the same time from places A and B respectively. They meet at a distance of one kilometer, how many kilometers are there between A and B?
从A地到B地，甲车需10个小时，乙车需8个小时，现甲、乙两车分别从A、B两地同时相向而行，而在距A、B两地中点40千米处相遇，求A、B两地相距多少千米？
<gadget id="calculator">1 / 8</gadget>
<output>1/8 = around 0.125</output>

<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">(1/8) - (1/10)</gadget>
<output>1/40 = around 0.025</output>

<gadget id="calculator">(1/10) + (1/8)</gadget>
<output>9/40 = around 0.225</output>

<gadget id="calculator">1 / (9/40)</gadget>
<output>40/9 = around 4.444444</output>

<gadget id="calculator">(1/40) * (40/9)</gadget>
<output>1/9 = around 0.111111</output>

<gadget id="calculator">2 / (1/9)</gadget>
<output>18</output>

<gadget id="calculator">40 * 18</gadget>
<output>720</output>

<result>720</result>