To celebrate the Olympic Games, a factory needs to make a batch of colorful balls. Workshop A takes 10 hours to make it alone, and workshop B takes 8 hours to make it alone. How many hours would it take if they worked together?
为了庆祝奥运，某工厂要制作一批七彩球，甲车间单独做要用10小时，乙车间单独做要用8小时．如果他们合做要多少小时完成？
<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

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

<gadget id="calculator">(1/10) + (1/8)</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>