A project can be completed by A alone in 8 hours, and B can complete 30 projects per hour. Now A and B are working together. When it is completed, A has done (5/8) of this project. How many pieces has B done?
一项工程，甲单独做8小时完成，乙每小时做30个．现在甲乙二人合做，完成时，甲做了这项工程的(5/8)，乙做了多少个？
<gadget id="calculator">5 / 8</gadget>
<output>5/8 = around 0.625</output>

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

<gadget id="calculator">(5/8) / (1/8)</gadget>
<output>5</output>

<gadget id="calculator">30 * 5</gadget>
<output>150</output>

<result>150</result>