The distance between A and B is 60 kilometers. Xiaoming and Xiaohua set off from the two places at the same time and walk towards each other. Xiaoming travels 7 kilometers per hour, Xiaohua travels 8 kilometers per hour, and another puppy starts with Xiaohua. It quickly met Xiao Ming, then returned and met Xiao Hua again, running back and forth like this, the dog ran 20 kilometers per hour, until the two met, how many kilometers did the puppy run in total?
甲乙两地相距60千米，小明与小华同时从两地出发，相向而行，小明每小时行7千米，小华每小时行8千米，另有一条小狗与小华一同出发，它很快遇到了小明，然后返回又遇到了小华，就这样来回地跑，狗每小时跑20千米，直到两人相遇，小狗一共跑多少千米？
<gadget id="calculator">7 + 8</gadget>
<output>15</output>

<gadget id="calculator">60 / 15</gadget>
<output>4</output>

<gadget id="calculator">4 * 20</gadget>
<output>80</output>

<result>80</result>