The machine factory plans to produce a batch of parts within 13 days. After the reform and opening up, due to the efforts of the workers to improve the technology, 35 more than the original plan were produced every day, and the task was completed in 8 days. How many pieces of this batch of parts were originally planned to be produced per day.
机器厂计划13天生产一批零件．改革开放后，由于工人努力改进技术，每天比原计划多生产35个，8天就完成任务．这批零件原计划每天生产多少个．
<gadget id="calculator">35 * 8</gadget>
<output>280</output>

<gadget id="calculator">13 - 8</gadget>
<output>5</output>

<gadget id="calculator">280 / 5</gadget>
<output>56</output>

<result>56</result>