George can do some work in 8 hours, Paulcan do the same work in 10 hours while Hiari can do the same work in 12 hours. All the three of them start working at 8 a.m. while George stops works at 10 a.m and remaining two complete the work. Approximately at what time will the work be finished?
A)12 noon B)1 pm C)12:30 pm D)11:30 am E)None of these

• G can do the work in 1 hour = 1/8 of the work
  
  P can do the work in 1 hour = 1/10 of the work
  
  H can do the work in 1 hour = 1/12 of the work
  
  Total work in 1 hour = 1/8 + 1/10 +1/12 = 37/120
  Total work in 2 hours = 37/60
  
  Remaining work = 1 - 37/60 = 23/60
  
  P & H 's total work in 1 hour is = 1/10 + 1/12 = 11/60
  
  11/60 work in 1 hour
  
  so, 23/60 work in (60/11) * (23/60) = 2 hours (approximate)
  
  The work will be finished approximately (10 + 2) = 12 noon
  
  Therefore, the answer is option A.
• 3 years agoHelpfull: Yes(2) No(0)
• George's one day work=1/8
  Paul's ......=1/10
  Hiari= 1/12
  there 2 hrs work= 2{1/8+1/10+1/12}= 2x37/120= 37/60
  remaining work=1-37/60=23/60
  Paul and Hiari did the remaining work= 23/60-{1/10+1/12}=23/60-11/60=12/60=1/5
  time taken 8+5=13 , hence th e work will be finished by 1p.m
• 4 years agoHelpfull: Yes(1) No(6)
• lcm of 8,10,12 is 120
  
  efficiency of :
  
  George is 15
  
  Paul is 12
  
  hari is 10
  
  then
  
  all the 3 work in first 2 hrs
  
  2(15+12+10)+x(12+10)=120
  
  x=2.09
  
  tot time from 9 am is 4.09 or 4
  
  so 1 pm
• 3 years agoHelpfull: Yes(1) No(2)
• Total work to be done = lcm(8,10,12) = 120
  respective efficiencies of george, paul and hilari = 15, 12, 10
  work done by all 3 for 2 hours ( 8 a.m. to 10 a.m.) = 37 x 2 = 74
  work remaining = 120 - 74 = 46
  46 work done by paul and hilari in ---- 46/(12 + 10) hrs = approx 2 hrs 16 mins
  so it will be finished by 12:16 pm.
  I would go for option E
• 3 years agoHelpfull: Yes(0) No(3)
• let total work = 120units
  george does his work in 8 hours , his capacity=120/8=15units /hour.
  paul does his work in 10 hours, his capacity =120/10=12units/hour.
  hiari does his work in 12 hours, his capacity=120/12=10units/hour.
  All 3 started at 9 am and worked upto 11 am. So total work done upto 11 am = 2 x (15 + 12 + 10) = 74
  Remaining work = 120 - 74 = 46
  Now this work is to be done by paul and hari. 46 / (12 + 10) = 2 hours (approx)
  So work gets completed at 1 pm
• 3 years agoHelpfull: Yes(0) No(1)
• A) 12 noon
• 3 years agoHelpfull: Yes(0) No(1)
• This is simple as much of calculation
  Their differences of hours is 2hrs
  When work start at 8am
  A took 2hr to complete with time 10am
  As same B took (2hr + differences) is 4hr from 8am , it will 11am the work will be completed by B
  As same as C ( 2hr+ 2hr+ 2hr) differences between from A,B. So totally 6hr should be added . When C start work at 8am , he will complete the work by 1pm.
• 3 years agoHelpfull: Yes(0) No(0)