The distance between the east and west cities is 75 kilometers. Xiaoming walks from east to west at 6.5 kilometers per hour; Xiaoqiang walks from west to east at 6 kilometers per hour; Xiaohui rides a bicycle from east to west at 15 kilometers per hour. km. The three started at the same time. On the way, Xiaohui met Xiaoqiang, turned back and rode eastward, met Xiaoming and rode westward, and went back and forth in this way until the three met on the way. How many kilometers did Xiaohui travel in total? How many
东、西两城相距75千米，小明从东向西走，每小时走6.5千米；小强从西向东走，每小时走6千米；小辉骑自行车从东向西每小时骑行15千米．3人同时动身，途中小辉遇见小强又折回向东骑，遇见小明又向西骑，这样往返，直到3人在中途相遇为止，则小辉共走了多少千米？多少
<gadget id="calculator">6.5 + 6</gadget>
<output>12.5</output>

<gadget id="calculator">75 / 12.5</gadget>
<output>6</output>

<gadget id="calculator">6 * 15</gadget>
<output>90</output>

<result>90</result>