It takes 15 days for teams A and B to build a canal together. The work efficiency ratio of teams A and B is 2:3. How many days will it take for team B to build this canal alone?
甲、乙两队合修一条水渠需要15天，甲、乙两队的工作效率比是2：3，如果乙队单独修这条水渠需要多少天？
<gadget id="calculator">1 / 15</gadget>
<output>1/15 = around 0.066667</output>

<gadget id="calculator">2 + 3</gadget>
<output>5</output>

<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">(1/15) * (3/5)</gadget>
<output>1/25 = around 0.04</output>

<gadget id="calculator">1 / (1/25)</gadget>
<output>25</output>

<result>25</result>