The distance from home to school is 1000 meters. My elder brother and younger sister walk to school. My younger sister walks 40 meters per minute, while my elder brother walks 65 meters per minute. The younger sister goes first, and after walking 180 meters, the older brother sets off. How many minutes will it take for the older brother to catch up with the younger sister?
家到学校的距离是1000米，哥哥和妹妹走着去上学，妹妹每分钟走40米，哥哥每分钟走65米．妹妹先走，走了180米后，哥哥才出发，哥哥多少分钟后能追上妹妹？
<gadget id="calculator">65 - 40</gadget>
<output>25</output>

<gadget id="calculator">180 / 25</gadget>
<output>36/5 = around 7.2</output>

<result>36/5 = around 7.2</result>