The walking speeds of A, B, and C are: A walks 90 meters per minute, B walks 75 meters, and C walks 60 meters per minute. A and C start from the west end of a long street, and B start from the east end of the long street at the same time and walk towards each other. It is exactly 4 minutes after A and B meet that B and C meet. What is the length of this long street in meters?
甲、乙、丙三人步行的速度分别是：每分钟甲走90米，乙走75米，丙走60米．甲、丙从某长街的西头、乙从该长街的东头同时出发相向而行，甲、乙相遇后恰好4分钟乙、丙相遇，那麽这条长街的长度是多少米？
<gadget id="calculator">75 + 60</gadget>
<output>135</output>

<gadget id="calculator">4 * 135</gadget>
<output>540</output>

<gadget id="calculator">90 - 60</gadget>
<output>30</output>

<gadget id="calculator">540 / 30</gadget>
<output>18</output>

<gadget id="calculator">90 + 75</gadget>
<output>165</output>

<gadget id="calculator">18 * 165</gadget>
<output>2_970</output>

<result>2_970</result>