A and B start from A and B at the same time and walk toward each other, and the meeting point is 640 meters away from the midpoint. It is known that the speed of A and the speed of B are 2:3, and A travels 80 meters per minute. Find the distance between places A and B.
甲、乙两人分别从A、B两地同时出发相向而行，相遇点距中点640米．已知甲的速度与乙的速度的2：3，甲每分钟行80米．求A、B两地的路程．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">2 + 3</gadget>
<output>5</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(1/2) - (2/5)</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">640 / (1/10)</gadget>
<output>6_400</output>

<result>6_400</result>