A, B, and C are three people. A walks 20 meters per minute, B walks 22.5 meters per minute, and C walks 25 meters per minute. A and B depart from East Town, and C departs from West Town at the same time. When C encounters B, he meets A 10 minutes later. How many meters are there between the two towns?
甲、乙、丙三人，甲每分钟走20米，乙每分钟走22.5米，丙每分钟走25米．甲、乙从东镇，丙从西镇同时相向出发，丙遇到乙后再过10分钟遇到甲，两镇相距多少米？
<gadget id="calculator">20 + 25</gadget>
<output>45</output>

<gadget id="calculator">22.5 - 20</gadget>
<output>2.5</output>

<gadget id="calculator">10 / 2.5</gadget>
<output>4</output>

<gadget id="calculator">22.5 + 25</gadget>
<output>47.5</output>

<gadget id="calculator">45 * 4 * 47.5</gadget>
<output>8_550</output>

<result>8_550</result>