There is a batch of parts that are jointly completed by A and B. Originally, A planned to make 50 more parts than B, but B actually made 60 fewer parts than planned. The total number made by B is 20 more than (3/5) the total number actually made by A. How many parts are there in this batch?
有一批零件由甲、乙两人合作完成，原计划甲比乙多做50个，结果乙实际做的比计划做的少60个．乙做的总数比甲实际做的总数的(3/5)多20个．问这批零件共有多少个？
<gadget id="calculator">60 * 2</gadget>
<output>120</output>

<gadget id="calculator">50 + 120 + 20</gadget>
<output>190</output>

<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">1 - (3/5)</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">190 / (2/5)</gadget>
<output>475</output>

<gadget id="calculator">475 - 170</gadget>
<output>305</output>

<gadget id="calculator">305 + 475</gadget>
<output>780</output>

<result>780</result>