Two workers, A and B, process the same number of parts, because A's efficiency is 25% higher than that of B, so A starts work 10 minutes later than B and finishes 20 minutes earlier than B. So how many minutes does it take B to complete the task of machining the part?
甲乙两名工人加工同样多的零件，因为甲的效率比乙高25%，因此甲比乙晚10分钟开工而比乙提前20分钟完工．那么乙完成加工零件的任务要用多少分钟？
<gadget id="calculator">10 + 20</gadget>
<output>30</output>

<gadget id="calculator">5 - 4</gadget>
<output>1</output>

<gadget id="calculator">30 / 1</gadget>
<output>30</output>

<gadget id="calculator">30 * 5</gadget>
<output>150</output>

<result>150</result>