Dongchai Machinery Factory needs to produce 700 machine tools. It has been in production for two months, with an average monthly production of 140 machines. If the remaining ones produce 70 machines per month, how many more months will they have to produce?
东柴机械厂要生产700台机床，已经生产了两个月，平均每月生产140台，剩下的如果每月生产70台，还要生产几个月？
<gadget id="calculator">140 * 2</gadget>
<output>280</output>

<gadget id="calculator">700 - 280</gadget>
<output>420</output>

<gadget id="calculator">420 / 70</gadget>
<output>6</output>

<result>6</result>