Y can do a work in 2/3 the time it takes X. Z can do the same work in ¾ the time it takes Y.When all
three are typing at the same time what fraction of their total work does Y do
a)1/3 b)4/13 c)9/23 d)8/29

• b ans
  given y=2/3x
  z=3/4y =>z=3/4*2/3x=1/2x
  x+y+z=(1+2/3+1/2)x=13/6x
  =>total/y=>(13/6)/(2/3)=13/4
  :ans 4/13
  
  
• 8 years agoHelpfull: Yes(16) No(9)
• given the ratio of the time of y and x is 2/3 : 1
  therefore the ratio of speed of the x and y becomes 2 : 3.
  similarly the ratio of the speed of the z and y given as 4 : 3
  therefore the speed of the y and z becomes 3 : 4.
  now , comparing the ratio of the x,y and z
  it becomes 2: 3 :: 3 : 4
  hence the y is doing 3/9 hence it is doing 1/3 work.
• 8 years agoHelpfull: Yes(16) No(20)
• time ratio of X : Y : Z is 1 : 2/3 : 1/2
  work ratio will be 1 : 3/2 : 2 or 2: 3: 4
  work done by Y is 3/9 or 1/3.
• 8 years agoHelpfull: Yes(5) No(2)
• Time Taken by Y = (2 *100)/3 = 66.66 unit.
  Time taken by Z = (3 * 66.66)/4 = 50 unit.
  Ratio of time of X, Y and Z = 100 : 66.66 : 50.
  Fraction of work Y do = 66.66/(100 + 66.66 +50) = 0.307 = 4/13.
• 8 years agoHelpfull: Yes(5) No(2)
• let x take 6k time
  y takes 4k time
  and z takes 3k time
  
  take lcm ,so total work is is 12k
  
  Rate of work(unit of work done in one day)
  
  x->(12k/6k)=2
  similarly
  y->3
  z->4
  
  for one day total work done 2+3+4
  
  out of which y contribution 3
  
  so fraction is 3/(2+3+4)=9
  
  ------------------------------------
  
  For those getting answer as 4/13
  
  You have added time taken by x,y,z and taken it to be 1 unit work
  doing this is wrong ,in math units of lhs and rhs must always be similar thus you cannot have equate time and work.
  
  y does not do 2/3 work ,it does whole work in 2/3 time of x
  similarly z does whole work in 1/2 time of x not 1/2 work.
• 4 years agoHelpfull: Yes(2) No(0)
• b)4/13 ==>correct answer
• 8 years agoHelpfull: Yes(1) No(1)
• Anand is right...Naveen has done addition considering tym & not SPEED=WORK/DAY...We can only perform addition & subtration with WORK/DAY
• 8 years agoHelpfull: Yes(0) No(2)
• Y:X = 2:3 and Z:Y=3:4 from the question given.Now find the ratio for X:Y:Z which is 12:8:6 then Y=8/(12+8+6) which is 4/13
• 5 years agoHelpfull: Yes(0) No(2)
• how answer will be 1/3,can you explain anand jha and ashish singh???in my opinion answer will be 4/13...
• 4 years agoHelpfull: Yes(0) No(0)
• 4/13
  ..
  ....
• 3 years agoHelpfull: Yes(0) No(0)