The workshop needs to process 4,700 parts, 150 parts are processed every day. When there are still 200 parts left to be processed, how many days has the workshop been processing?
车间要加工4700个零件，每天加工150个，当还剩200个没加工完时，这个车间已经加工了多少天？
<gadget id="calculator">4_700 - 200</gadget>
<output>4_500</output>

<gadget id="calculator">4_500 / 150</gadget>
<output>30</output>

<result>30</result>