A woman lives in a 36 floor building. There is a lift in that building. When she leaves her aprtment and goes to lift,there are 3 times chances lift will take her up than take her down(3:1,up:down)..On which floor she lives?

• Let the woman Lives on X numberth floor.
  P(down)=X/36
  and P(up)=(36-X)/36
  acc. to question P(up) = 3*P(down)
  => (36-X)/36 = 3 * X/36
  =>X=9 answer
• 9 years agoHelpfull: Yes(1) No(0)
• answer 9 is wrong bcoz there are 35 floor+ ground floor counting 36 floor building. so the ans will be 9-1=8th floor.
• 9 years agoHelpfull: Yes(1) No(6)
• I answered 10th floor.
• 9 years agoHelpfull: Yes(0) No(0)
• In vinsol test paper of 13 aug the marked this ans 9th floor wrong
• 9 years agoHelpfull: Yes(0) No(0)
• 27 is d ans
  
• 9 years agoHelpfull: Yes(0) No(0)
• 3:1 being the ratio, (3/4)*36 =27, which gives 36-27=9.The chances are in the ratio of 3:1 = 27:9. Therefore 9th floor seems plausible :D.
• 9 years agoHelpfull: Yes(0) No(0)
• 9th floor
  
• 9 years agoHelpfull: Yes(0) No(0)
• Ans 12 36/3 = 12
• 9 years agoHelpfull: Yes(0) No(0)
• answer is 8
• 8 years agoHelpfull: Yes(0) No(0)
• Given that there are 3 times the chances that the lift will take the woman up than take her down.
  Up:Down=3:1
  It can be inferred that the probability that the lift takes her up = 3 / (3+1) = 3/4
  And the probability that the lift takes her down from her floor = 1 / (3+1) = 1/4
  Now let the woman live on floor number x.
  Considering total number of floors as 36, excluding the ground floor.
  Then the lift can take her 36-x floors up or x floors down. ( if you are on the 4th floor, you can go down to 3rd, 2nd , 1st, or ground floor, that is go down to 4 floors)
  So up : down = 3 / 1 = (36 – x) / x
  Or x=9
  Or it can also be done like this:
  probability of the event the lift takes her down = 1 / 4 = x / 36
  =>x=9.
  So the woman lives on the 9th floor.
• 4 years agoHelpfull: Yes(0) No(0)