A and B travel from A to B, and C travels from B to A. They set off at the same time, A rides a bicycle at 8 kilometers per hour, and C rides a bicycle at 10 kilometers per hour. A and C meet each other after 5 hours, and after another hour, B and C meet. Find the speed of B.
甲、乙两人从A地到B地，丙从B地到A地．他们同时出发，甲骑车每小时行8千米，丙骑车每小时行10千米，甲丙两人经过5小时相遇，再过1小时，乙、丙两人相遇．求乙的速度．
<gadget id="calculator">8 + 10</gadget>
<output>18</output>

<gadget id="calculator">5 + 1</gadget>
<output>6</output>

<gadget id="calculator">5 / 6</gadget>
<output>5/6 = around 0.833333</output>

<gadget id="calculator">18 * (5/6)</gadget>
<output>15</output>

<gadget id="calculator">15 - 10</gadget>
<output>5</output>

<result>5</result>