project needs 8 hours to be completed by A alone, and B can only complete 80% of A's workload in the same time. If two people work together, how many hours will it be completed?
一项工程，甲独做要8小时完成，乙在相同的时间内只能完成甲工作量的80%，二人合做，几小时完成？
<gadget id="calculator">1 / 8</gadget>
<output>1/8 = around 0.125</output>

<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">(1/8) * (4/5)</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">(1/8) + (1/10)</gadget>
<output>9/40 = around 0.225</output>

<gadget id="calculator">1 / (9/40)</gadget>
<output>40/9 = around 4.444444</output>

<result>40/9 = around 4.444444</result>