A project can be completed by A in 12 days and by B in 15 days. By what percentage is A's work efficiency higher than B's work efficiency?
一项工程，甲单独做需12天完成，乙单独做需15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 / 12</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">1 / 15</gadget>
<output>1/15 = around 0.066667</output>

<gadget id="calculator">(1/12) - (1/15)</gadget>
<output>1/60 = around 0.016667</output>

<gadget id="calculator">(1/60) / (1/15)</gadget>
<output>1/4 = around 0.25</output>

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