Production of a batch of parts can be completed in 10 days if A and B cooperate. If A can complete it in 18 days, how many days will it take if B does it alone?
生产一批零件，甲乙合作10天可以完成，若甲独做18天可以完成，若乙独做要多少天才能完成．
<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">1 / 18</gadget>
<output>1/18 = around 0.055556</output>

<gadget id="calculator">(1/10) - (1/18)</gadget>
<output>2/45 = around 0.044444</output>

<gadget id="calculator">1 / (2/45)</gadget>
<output>45/2 = around 22.5</output>

<result>45/2 = around 22.5</result>