A and B process 240 parts each, and they start at the same time. When A completes half of the task, B makes 20 more parts than A. A makes 5 fewer parts per hour than B on average. How many parts does B make on average per hour?
甲乙两人各加工240个零件，他们同时动工，当甲完成任务一半时，乙比甲多做了20个．甲平均每小时比乙少做5个零件．乙平均每小时做几个零件？
<gadget id="calculator">240 / 2</gadget>
<output>120</output>

<gadget id="calculator">120 + 20</gadget>
<output>140</output>

<gadget id="calculator">20 / 5</gadget>
<output>4</output>

<gadget id="calculator">140 / 4</gadget>
<output>35</output>

<result>35</result>