A project originally planned to invest 800,000 yuan, but actually invested 1 million yuan. What percentage is the actual extra investment?
一项工程，原计划投资80万元，实际投资100万元．实际多投资百分之几？
<gadget id="calculator">100 - 80</gadget>
<output>20</output>

<gadget id="calculator">20 / 80</gadget>
<output>1/4 = around 0.25</output>

<result>1/4 = around 0.25</result>