The master and the apprentice process a batch of parts, the apprentice processed 320 pieces, which is 20 less than the master's (2/3), how many parts are there in this batch?
师徒两人加工一批零件，徒弟加工了320个，比师傅的(2/3)少20个，这批零件有多少个？
<gadget id="calculator">320 + 20</gadget>
<output>340</output>

<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">340 / (2/3)</gadget>
<output>510</output>

<gadget id="calculator">510 + 320</gadget>
<output>830</output>

<result>830</result>