A and B ride bicycles from east to west at the same time and meet each other in 8 hours. If A travels 1 km less per hour and B travels 3 km more per hour, they can meet each other in 7 hours. How many kilometers is the distance between the east and the west.
甲乙两人骑车同时从东、西相向而行，8小时相遇，若甲每小时少行1千米，乙每小时多行3千米，则7小时可相遇．东西两地相距多少千米．
<gadget id="calculator">3 * 7</gadget>
<output>21</output>

<gadget id="calculator">21 - 7</gadget>
<output>14</output>

<gadget id="calculator">8 - 7</gadget>
<output>1</output>

<gadget id="calculator">14 / 1</gadget>
<output>14</output>

<gadget id="calculator">14 * 8</gadget>
<output>112</output>

<result>112</result>