mobile phone factory needs to produce a batch of mobile phones, and has already produced 5,000 units. The remaining unproduced parts are 400 units less than the total number (1/3) that needs to be produced. How many mobile phones does the mobile phone factory need to produce?
某手机厂需要生产一批手机，已经生产了5000部，剩余未生产的部分比需要生产的总数的(1/3)少400部，该手机厂需要生产多少部手机？
<gadget id="calculator">5_000 - 400</gadget>
<output>4_600</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 - (1/3)</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">4_600 / (2/3)</gadget>
<output>6_900</output>

<result>6_900</result>