The turnover of a certain supermarket last month was 4 million yuan, and the business tax was paid at a rate of 5%. How much business tax should this supermarket pay last month?
某超市上个月的营业额是400万元，按5%的税率缴纳营业税，这个超市上个月应缴纳营业税多少万元．
<gadget id="calculator">5 / 100</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">400 * (1/20)</gadget>
<output>20</output>

<result>20</result>