The vegetable farm uses the same truck to transport vegetables. A total of 640 boxes were transported with 4 vehicles first, and then all of them can be transported with 3 vehicles. How many boxes of vegetables did the farm ship in total?
菜场用相同的卡车运蔬菜．先用4辆车共运走了640箱，再用3辆车就可全部运完．菜场一共运了多少箱蔬菜？
<gadget id="calculator">640 / 4</gadget>
<output>160</output>

<gadget id="calculator">4 + 3</gadget>
<output>7</output>

<gadget id="calculator">160 * 7</gadget>
<output>1_120</output>

<result>1_120</result>