. George takes 30 days to do a piece of work and Mark takes 45 days for the same work. For the first 15 days only George works. Then Mark also joins him. Find the time taken to complete the entire work.

• George 1 day work= 1/30
  Mark 1 day work= 1/45
  
  George 15 day work= 15*1/30 =1/2
  Work remaining= 1-1/2 =1/2
  George + Mark 1 day work= 1/30 + 1/45 =1/18
  
  Number of day required to complete 1/2 work= (1/2)/(1/18)= 9 days
  So total days required to complete the work is 15+9= 24 days.
• 10 years agoHelpfull: Yes(40) No(1)
• LCM(30,45)=90 units of work
  So, Mark does 90/45=2 units
  George does 90/30= 3 units for 15 mins George does 45 units
  rest 45 units is done by both in 90/(3+2)=9 days
  So,ans is 15+9 =24 days
• 10 years agoHelpfull: Yes(5) No(0)
• total time taken to complete the entire work is 24 days
• 10 years agoHelpfull: Yes(4) No(0)
• 9 more days
• 10 years agoHelpfull: Yes(2) No(0)
• george takes 30 days
  mark takes 45 days
  total unit of work is LCM of 30 and 45 i.e 90
  means george does 3 units per day and mark does 2 units per day.
  for the first 15 days george completes 45 unit i.e 3*15
  now remaining 45 units completed by both will be in 9 more days
  i.e 2+3=5 unit both can do in single day and they take 9 days to complete 45 unit
  so ans is total 24 days to complete the work. (15+9=24)
• 10 years agoHelpfull: Yes(1) No(0)
• this time of problem ,,we can solve by using pecentage method
  work done by george in one day=100/30=3.33%
  work done by mark in one day=100/45=2.22%
  
  work done by both in one day=3.33+2.22=5.55%
  according to question george works alone with 15 day....so work done by george in 15 days=3.33*15=49.95%
  remaining work =100-49.95=50.05
  work is done by george and mark in one day=5.55%
  so in 9 day remaining work is done by both
  finally day=15+9=24
• 10 years agoHelpfull: Yes(1) No(0)
• George = 30 days.
  Mark= 45 days
  
  Let X be the total time taken to complete the entire work.
  As given george works first 15 days alone n after the 15 days mark joins him, therefore using this make a equation,
  (15+(X-15))/30 + (X-15)/45 = 1
  By SOLVING THIS EQUATION YOU WILL GET,
  X=24 days
• 10 years agoHelpfull: Yes(1) No(1)
• 24d is the ans
• 10 years agoHelpfull: Yes(0) No(0)
• 24day half work done by george so...half work done by both
• 10 years agoHelpfull: Yes(0) No(0)
• 15+ 9 = 24 so total 24 days taken
• 10 years agoHelpfull: Yes(0) No(0)
• 24,,,,,,sjmloh
  
• 9 years agoHelpfull: Yes(0) No(0)
• Ans is:24
  George one day work=1/30
  Mark one day work=1/45
  George+Mark one day work=1/30+1/45=5/90=1/18
  First 15 days work=15*1/30=1/2
  Remaining work=1-1/2=1/2
  Time taken to complete the entire work=1/2/1/18=9
  Total time taken to complete the work is 9+15=24...
• 9 years agoHelpfull: Yes(0) No(0)