Ding Xiaohua and Ding Daming both go from A to B at the same time. Ding Xiaohua walks 60 meters per minute, and Ding Daming walks 90 meters per minute. Ding Daming returns immediately after arriving at B and meets Ding Xiaohua. When they meet, Ding Xiaohua still needs to walk It takes 3 minutes to reach point B. How many miles is the distance between A and B?
丁小华和丁大明两人同时从A地去B地，丁小华每分钟行60米，丁大明每分钟行90米，丁大明到达B地后立即返回，并与丁小华相遇，相遇时，丁小华还需行3分钟才能到达B地．AB两地相距多少千米．
<gadget id="calculator">90 - 60</gadget>
<output>30</output>

<gadget id="calculator">2 / 30</gadget>
<output>1/15 = around 0.066667</output>

<gadget id="calculator">60 * 3 * (1/15)</gadget>
<output>12</output>

<gadget id="calculator">12 + 3</gadget>
<output>15</output>

<gadget id="calculator">15 / 1_000</gadget>
<output>3/200 = around 0.015</output>

<gadget id="calculator">60 * (3/200)</gadget>
<output>9/10 = around 0.9</output>

<result>9/10 = around 0.9</result>