8 identical machines, working alone and at their constant rates, take 6 hours to complete a job lot. How long would it take for 2 such machines to perform the same job?  Select the correct option.
A) 2.25 hours B) 8.75 hours C) 12 hours D) 24 hours E) 16 hours
Let each machine do 1 unit of work for 1 hour   8 machines --&gt; 8 units of work in 1 hour   For 6 hours = 8*6= 
<gadget id="calculator">8*6</gadget>
<output>48</output>
48 Units of total work is done.   Now this 48 Units of total work must be done by 2 machines   2 units of work(2 machines) ---&gt; 1 hour   for 48 Units of work   2*24 ---&gt; 1*24 hours   24 hours 24 hours
<result>D</result>
8 identical machines, working alone and at their constant rates, take 6 hours to complete a job lot. How long would it take for 2 such machines to perform the same job?