P can complete a work in 12 days working 8 hours a day,Q can complete the same work in 8 days working 10 hours a day. If both P and Q work together, working 8 hours a day, in how many days can they complete the work?
A. 5x5/11 B. 5x6/11
C. 6x5/11 D. 6x6/11

• Ans is A)5 5/11 days
  First we have to convert into hours it is easy to solve the question
  so p ==> 12 * 8 = 96 h
  Q ==> 8 * 10 = 80 h
  p+Q= 1/96 + 1/80 = 11/480
  (ie) 480/11 h
  per day 8 hours so 480/11*8 = 60/11 days (ie) 5 5/11 days
• 12 years agoHelpfull: Yes(27) No(2)
• p can complete a work in 12*8=96 hours
  q can complete a work in 8*10=80 hours
  
  p's 1 hour work = 1/90
  q's 1 hour work = 1/80
  
  (p+q) 1 hour work = (1/90+1/80)=11/480
  
  p and q can complete the work in 480/11 hours.
  
  working 8 hours a day then (480/11)*(1/8)= 60/11 = 5*5/11
  
  Answer is A.
• 10 years agoHelpfull: Yes(6) No(2)
• Ans is A)
  first we have to convert work of Q for 8hrs: (10*8)/8=10 days per 8hrs
  now 1/P+1/Q=1/12+1/10=11/60 =>5 5/11
• 9 years agoHelpfull: Yes(2) No(1)