How many 20-yuan renminbi can be exchanged for 8 pieces of 50-yuan renminbi?
8张50元的人民币可以兑换多少张20元的人民币．
<gadget id="calculator">8 / 20</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">50 * (2/5)</gadget>
<output>20</output>

<result>20</result>