A project can be completed in 20 days by A alone, and 25 days by B alone. By what percentage is A's work efficiency higher than B's work efficiency?
一项工程，甲独做需20天完成，乙独做需25天完成．甲的工作效率比乙的工作效率高百分之几？
<gadget id="calculator">1 / 20</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">1 / 25</gadget>
<output>1/25 = around 0.04</output>

<gadget id="calculator">(1/20) - (1/25)</gadget>
<output>1/100 = around 0.01</output>

<gadget id="calculator">(1/100) / (1/25)</gadget>
<output>1/4 = around 0.25</output>

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