Processing a batch of parts, A alone takes 5 hours to complete, and B alone takes 8 hours to complete, how much lower is the efficiency of B than that of A?
加工一批零件，甲单独做要5小时完成，乙单独做要8小时完成，乙的效率比甲的效率低百分之几？
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 / 8</gadget>
<output>1/8 = around 0.125</output>

<gadget id="calculator">(1/5) - (1/8)</gadget>
<output>3/40 = around 0.075</output>

<gadget id="calculator">(3/40) / (1/5)</gadget>
<output>3/8 = around 0.375</output>

<result>3/8 = around 0.375</result>