A project can be completed in 15 hours, and the work efficiency of B is 25% higher than that of A. If two people work in turn in the order of A, B, A, B... for 1 hour, how long will it take to complete the project?
一件工程，甲15小时可以完成，乙的工效比甲高25%，若两人以甲、乙、甲、乙…的顺序轮流工作1小时，多长时间可以完成这项工程？
<gadget id="calculator">1 / 15</gadget>
<output>1/15 = around 0.066667</output>

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

<gadget id="calculator">1 + (1/4)</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">(1/15) * (5/4)</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">(1/15) + (1/12)</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">(3/20) * 6</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">1 - (9/10)</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">(1/10) - (1/15)</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">(1/30) / (1/12)</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">12 + 1 + (2/5)</gadget>
<output>67/5 = around 13.4</output>

<result>67/5 = around 13.4</result>