Two people, A and B, ride bicycles from two places at the same time towards each other. A travels 15 kilometers per hour, and B travels 13 kilometers per hour. The two meet at a distance of 3 kilometers from the midpoint. Find the distance between the two places.
甲、乙二人同时从两地骑自行车相向而行，甲每小时行15千米，乙每小时行13千米，两人在距中点3千米处相遇，求两地的距离．
<gadget id="calculator">15 + 13</gadget>
<output>28</output>

<gadget id="calculator">3 * 2</gadget>
<output>6</output>

<gadget id="calculator">15 - 13</gadget>
<output>2</output>

<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">28 * 3</gadget>
<output>84</output>

<result>84</result>