From A to B is a 1000-meter downhill road, from B to C is a 3200-meter flat road, and from C to D is a 2500-meter uphill road. The downhill speed of Xiao Zhang is 100 m/min, the speed on the flat road is 80 m/min, and the uphill speed is 50 m/min. How many minutes does it take him to go back and forth from A to D?
从A到B是1000米下坡路，从B到C是3200米平路，从C到D是2500米上坡路．小张骑车的下坡速度是100米/分，平路速度是80米/分，上坡的速度是50米/分．他从A到D往返一趟共用多少分钟？
<gadget id="calculator">1_000 / 100</gadget>
<output>10</output>

<gadget id="calculator">3_200 / 80</gadget>
<output>40</output>

<gadget id="calculator">2_500 / 50</gadget>
<output>50</output>

<gadget id="calculator">1_000 / 50</gadget>
<output>20</output>

<gadget id="calculator">2_500 / 100</gadget>
<output>25</output>

<gadget id="calculator">10 + 40 + 50 + 20 + 40 + 25</gadget>
<output>185</output>

<result>185</result>