A batch of rice sold 320kg, and the rest is 20kg less than the original total (5/7). How many kilograms did this batch of rice originally have?
一批大米，卖出320kg，剩下的比原来总数的(5/7)少20kg，这批大米原来有多少千克？
<gadget id="calculator">320 - 20</gadget>
<output>300</output>

<gadget id="calculator">5 / 7</gadget>
<output>5/7 = around 0.714286</output>

<gadget id="calculator">1 - (5/7)</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">300 / (2/7)</gadget>
<output>1_050</output>

<result>1_050</result>