Raju, Rahim, Rajesh together can do a work in 5 days. Raju alone can do the work in 10 days and Rahim alone can do the same work in 20 days. Find in what time Rajesh alone can do that work?
Options: A) 10days B) 15days C) 20days D) 30days E) 18days
The required answer is = 5*10*20 / 10*20-5(10+20)   = 1000/50= 
<gadget id="calculator">1000/50</gadget>
<output>20</output>
20days   Answer is 20days
<result>C</result>
Raju, Rahim, Rajesh together can do a work in 5 days. Raju alone can do the work in 10 days and Rahim alone can do the same work in 20 days. Find in what time Rajesh alone can do that work?