A professional household raising rabbits raises 800 white rabbits, and the number of black rabbits is 20% less than that of white rabbits. How many white rabbits and black rabbits are there?
一个养兔专业户养白兔800只，黑兔比白兔少20%．白兔和黑兔共有多少只？
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">800 * (4/5)</gadget>
<output>640</output>

<gadget id="calculator">640 + 800</gadget>
<output>1_440</output>

<result>1_440</result>