A worker processes a batch of machine parts, completes (1/5) of the task on the first day, and completes the rest (1/3) on the second day. A total of 56 pieces were completed in the first two days. Question: How many parts are there in this batch?
一个工人加工一批机器零件，第一天完成了任务的(1/5)，第二天完成了剩下部分的(1/3)，前两天一共完成了56个．请问：这批零件共有几个？
<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">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(4/5) * (1/3)</gadget>
<output>4/15 = around 0.266667</output>

<gadget id="calculator">(1/5) + (4/15)</gadget>
<output>7/15 = around 0.466667</output>

<gadget id="calculator">56 / (7/15)</gadget>
<output>120</output>

<result>120</result>