A is thrice as good a workman as B and therefore is able to finish a job in 60 days less than B. Working together, they can do it in:

• The efficiency ratio of A:B=3:1
  Let B takes x days to complete the work
  Then A must take (x-60)days to complete the work
  Thus, the equation becomes:
  3(x-60)=1*x
  Solving , we get x=90 days( B takes to complete the job)
  Hencce A takes to complete the job in 30 days
  Working together, they do the work in one day=1/30+1/90=4/90
  Thus they together can complete the job in 90/4 days=22.5days
  
• 12 years agoHelpfull: Yes(15) No(2)
• Shortcut Method :
  A is K times as good a workman as B and therefore is able to finish a job in X days less than B. Working together, they can do it in
  
  ==> (K*X) / (K^2 -1) here K is How many times greater i.e.. 3 times , X is work days i.e.. 60 days
  ==> (3*60) /(3^2-1)
  ==> 180/8
  :- 22.5 days
• 8 years agoHelpfull: Yes(3) No(0)
• here we can see that a does 3 work and b does 1 work because a is thrice good than b.
  so we can solve this question with the help of ratio.
  here suppose b can finish the whole work in x days
  then a can do this in x-60 days.
  then,x-60/x=1/3
  (since 3a=1b hence a/b=1/3)
  after solving x=90 (b=90 because x=90)
  hence a=x-60=30
  so we will try to get 1 day work done by a and b=1/30+1/90
  after solving 2/45.
  this is one day work of a and b .
  hence whole work will done in 45/2 days
  ans=22 and 1/2 days.
• 9 years agoHelpfull: Yes(2) No(0)
• A:B=1:3 or A=(1/3)B or 3A=B ( A is thrice as good a workman as B )
  A-B=60
  A-3A=60 => 2A=60 => A=30 ( In the result of Time & Work problems there won't be Negative )
  Here A =30, SO B=90 ( As A is thrice efficient than B )
  
  Now they both can do the work in
  (1/30)+(1/90) Days
  => 4/90 Days => 90/4 Days => 22.5 Days
• 8 years agoHelpfull: Yes(2) No(0)
• 22.5 days is the solution
• 9 years agoHelpfull: Yes(0) No(0)
• a=x/3days
  b=x days
  x-x/3=60
  >x=90
  a=90/3=30days=1/30(work done by 1 day)
  b=90days=1/90(work done by 1 day)
  a+b=1/30+1/90=2/45(both done in 1 day)
  a and b together can complete the work in 45/2 =22.5days
• 8 years agoHelpfull: Yes(0) No(0)
• let efficiency of b=x and let b take the time to complete the work T
  then the efficiency of a will be=3x and A will take to complete the work=T-30
  so T*x=(T-30)*3*x
  after solving the eq. T=90and x=1
  so eff oa a=3 and b=1
  s0 total time they will take to complete the work=90/4=22.5 days
• 7 years agoHelpfull: Yes(0) No(0)
• Let A be X where as b = 3x.
  So,
  3x – x = 60.
  x = 30.
  a = 30, b = 90.
  
  Together they can do the work in 22 (1/2) days.
  http://callinterview.com/questions-answers/a-is-thrice-as-good-as-workman-as-b-and-therefore-is-able-to-finish-a-job-in-60-days-less-than-b-working-together-they-can-do-it-in/
• 7 years agoHelpfull: Yes(0) No(0)
• A=3B
  A:B=3:1 efficiency
  A:B=1:3 time
  2parts =60
  1 part =30
  A=30days
  B=90days
  A and B together= 1/30+ 1/60= 22.5 days
• 4 years agoHelpfull: Yes(0) No(0)