A workshop needs to produce a batch of parts. On average, 60 pieces are produced every day, and 350 pieces are left after 7 days. How many parts are in this batch?
一个车间要生产一批零件．平均每天要生产60个，7天后还剩下350个没有生产．这批零件共多少个？
<gadget id="calculator">7 * 60</gadget>
<output>420</output>

<gadget id="calculator">420 + 350</gadget>
<output>770</output>

<result>770</result>