Two cars AB start from A and B at the same time and drive towards each other. Car A travels 58 kilometers per hour, and car B travels 42 kilometers per hour. After 4 hours, the two cars meet and are separated by 20 kilometers. Find the distance between A and B the distance between.
AB两车同时从甲乙两地出发相向而行，A车每小时行驶58千米，B车每小时行驶42千米，经过4小时后两车相遇后又相距20千米，求甲乙两地之间的距离．
<gadget id="calculator">58 + 42</gadget>
<output>100</output>

<gadget id="calculator">100 * 4</gadget>
<output>400</output>

<gadget id="calculator">400 - 20</gadget>
<output>380</output>

<result>380</result>