and B are doing running training on the road between A and B. They start from A and B at the same time and run towards each other. B's speed is (3/5) of A's speed; A's speed when running the second full distance is reduced by (1/5) compared to running the first full distance, and B's speed when running the second full distance is faster than running the first The whole journey has been increased by 50%. It is known that the point where A and B meet for the second time is 257 meters away from the point where they met for the first time. Find the distance between A and B.
甲、乙两人在A、B间的公路上作跑步训练，他们同时从A、B两地出发相向而跑，每人跑完第一个全程之后，立即回头变速跑第二个全程，起初乙的速度为甲速度的(3/5)；甲跑第二个全程时的速度比跑第一个全程时减少了(1/5)，乙跑第二个全程时的速度比跑第一个全程时提高了50%，已知甲、乙两人第二次相遇点距第一次相遇点257米，求A、B两地间距离．
<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">1 + (3/5)</gadget>
<output>8/5 = around 1.6</output>

<gadget id="calculator">1 / (8/5)</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">(3/5) * (5/8)</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">1 - (3/8)</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">(5/8) / (3/5)</gadget>
<output>25/24 = around 1.041667</output>

<gadget id="calculator">1 / (8/5) / 1</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">(25/24) - (3/8)</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">(2/3) * (4/5)</gadget>
<output>8/15 = around 0.533333</output>

<gadget id="calculator">1 - (8/15)</gadget>
<output>7/15 = around 0.466667</output>

<gadget id="calculator">50 / 100</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 + (1/2)</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">(3/5) * (3/2)</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">(9/10) + (4/5)</gadget>
<output>17/10 = around 1.7</output>

<gadget id="calculator">(7/15) / (17/10)</gadget>
<output>14/51 = around 0.27451</output>

<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">(14/51) * (4/5)</gadget>
<output>56/255 = around 0.219608</output>

<gadget id="calculator">(8/15) - (3/8)</gadget>
<output>19/120 = around 0.158333</output>

<gadget id="calculator">(56/255) + (19/120)</gadget>
<output>257/680 = around 0.377941</output>

<gadget id="calculator">257 / (257/680)</gadget>
<output>680</output>

<result>680</result>