Two people, A and B, start from the same place and at the same time on the ring road by bicycle, and walk with their backs facing each other. It takes 60 minutes for A to walk around. It is known that 45 minutes after departure, A and B meet. If A and B meet, A goes in the opposite direction, and A and B meet again after a few minutes.
甲、乙两人骑自行车从环形公路上的同一地点、同一时间出发，背向而行．甲走一圈需60分钟．已知出发45分钟后，甲、乙两人相遇．如果甲、乙两人相遇后，甲反向而行，问几分钟后甲、乙两人再次相遇．
<gadget id="calculator">1 / 90</gadget>
<output>1/90 = around 0.011111</output>

<gadget id="calculator">1 / (1/90)</gadget>
<output>90</output>

<result>90</result>