if A alone does the work in 15 days,how much time will A and B take working together to complete the job,given that A is 30% more efficient than B?

• ratio of times taken by A and B is=100:130
  suppose B takes x days to do the work.
  100:130::15:x
  x=130*15/100=39/2.
  B's 1 day's work=2/39
  A's 1 day's work=1/15
  (A+B)'s 1 day's work=69/585
  A & B together can complete the work in 585/69 days..
• 8 years agoHelpfull: Yes(25) No(27)
• efficiency ratio of A:B=13:10
  time ratio of A:B=10:13
  so,10:13=15:x
  so,x=39/2
  so,time taken by A=15(given)
  time taken by B=39/2(calculated)
  efficiency 1/15:2/39=13:10 [taking LCM(15,23)=195 which is total work]
  Now,(A+B) does 23 unit in 1 day
  195 unit in 195/23 days(ans)
• 8 years agoHelpfull: Yes(23) No(1)
• A's 1 day work=1/15
  A is 30% more efficient than b
  So B's 1 day work= 1/15-(30/100*1/15)
  =7/150
  S0 A+B 's 1 day work=1/15+7/150=17/150
  so they will take 150/17 days .
  
• 8 years agoHelpfull: Yes(11) No(8)
• time taken by a and b = 100:130 :: 15:x
  ad = bc
  x=( 130*15)/100
  x= 39/2
  A's 1 day work = 1/15
  B's 1 day work = 2/39
  total = (1/15)+(2/39) = 23/ 195
  ans is 195/23
• 8 years agoHelpfull: Yes(10) No(1)
• I think all the solutions provided are a mistake.
  
  Let Time taken by B is x days.
  
  since A is 30% more efficient than B
  
  i.e.,if B takes 10 days then A sud take 7 days.
  
  Then, x+(30/100)x=15
  
  x=150/13.
  
  (A+B) combined 1 day's work=(1/15 + 13/150)=23/150
  
  Hence (A+B) can finish together in 150/23 days.
• 8 years agoHelpfull: Yes(8) No(6)
• efficency ratio=130:100
  since efficency inversely proportion to time
  Ratio of times taken by A and B = 100 : 130 = 10 : 13.
  Suppose B takes x days to do the work.
  Then, 10 : 13 :: 15 : x => x = (15 x 13)/10 => x =39/2
  A's 1 day's work = 1/15;
  B's 1 day's work = 2/39 .
  (A + B)'s 1 day's work=1/15+2/39=23/195
  Therefore, A and B together can complete the work in 195/23 days.
• 8 years agoHelpfull: Yes(5) No(2)
• let B=100;
  A 30 % more than B so A=300;
  A can do work in 15 days
  B---------------?
  100--------------?------B
  130--------------15----A
  100:130=?:15
  B=150/13
  A one day work 1/15
  B one day work 150/13
  A+B=1/15+13/150=23/150
  
• 8 years agoHelpfull: Yes(1) No(2)
• 585/65suppose B takes x days to do the work.
  100:130::15:x
  x=130*15/100=39/2.
  B's 1 day's work=2/39
  A's 1 day's work=1/15
  (A+B)'s 1 day's work=69/585
  A & B together can complete the work in 585/69 days.
• 6 years agoHelpfull: Yes(1) No(0)
• efficiency ratio of A:B=13:10
  time ratio of A:B=10:13
  so,10:13=15:x
  so,x=39/2
  so,time taken by A=15(given)
  time taken by B=39/2(calculated)
  (A+B)'S 1 day work =(1/15 +2/39) =6/65
  => 1 complete work done by (A+B)= 65/6 days
• 8 years agoHelpfull: Yes(0) No(4)
• ratio of times == 130:100
  if b takes x days
  130:100 :: 15 :x
  13x=150
  x =150/13
  => b takes 150/13 dayz
  a +b = 1/15 + 13/150 = 23/150 =>15/23 days
  
• 8 years agoHelpfull: Yes(0) No(4)
• @shalini kumari u made a mistake in finding LCM of 39 and 15
• 8 years agoHelpfull: Yes(0) No(0)
• ans= 195/23 days
• 8 years agoHelpfull: Yes(0) No(0)
• 195/23 is right
  
• 8 years agoHelpfull: Yes(0) No(0)
• AS A IS 30% EFFICIENT THEN RATIO OF A: B IS:-
  100:130 ~10:13
  
  A ALONE DOES IN 15 DAYS THEN TOTAL WORK WILL BE:-
  15*10=150 UNIT
  
  HENCE A AND B TOGETHER WILL DO IN :-
  150/10+23 =195/23 ~ 9 DAYS
• 7 years agoHelpfull: Yes(0) No(0)
• A=15days
  A+B=?
  consider
  B =100work in 1day
  then A=130 in 1day
  so,
  A+B=230 in 1day
  A=130*15 in 15days
  A+B= 130*15/230= 9days
• 7 years agoHelpfull: Yes(0) No(0)