Two pipes can fill a tank in 10hours and 12 hours respectively while a third, pipe empties the full tank in 20 hours. If all the three pipes operate simultaneously, in how much time will the tank be filled?

• Ans is 7.5
  let x be the time taken to fill wile three pipes are operating simultaniously
  then
  x(1/10+1/12-1/20)=1
  x=1/0.1333
  x=7.5 h
• 10 years agoHelpfull: Yes(13) No(3)
• ANSWER==> 7.5 hour
  1/10+1/12-1/20 = 16/120 = 2/15
  hence time taken to fill the tank = 17/2 = 7.5 hours
  
• 10 years agoHelpfull: Yes(5) No(3)
• ans is:
  (1/10+1/12)-1/20=15/2=7.5hr
  
• 10 years agoHelpfull: Yes(2) No(1)
• A+ - 10 hr
  B + - 12 hr
  c- - 20
  LCM = 60
  so A fills 6 part in 1 hr
  B fills 5 parts in 1 hr
  c empties 3 parts in 1 hr
  so 6+5-3 = 8 parts are filled in 1 hr if all three pipes are opened
  so it they will take 60/8 = 7*1/2 hr to fill the tank
• 10 years agoHelpfull: Yes(2) No(0)
• consider 120 lit capacity
  speed of a-> 12 l/h b-> 10 l/h and c-> -6 l/h
  hence per hour it takes 16 lit so 120/16=7.5 hours
  
• 10 years agoHelpfull: Yes(1) No(0)
• time to fill in 1hour=(1/10+1/12-1/20)=8/60
  tank will full=60/8hrs.i.e 7hrs 30 min.
• 10 years agoHelpfull: Yes(1) No(0)
• let x be the product price
  market price is rs 8400
  now
  productprice+tax = market price
  x+(7/200)*x=8400
  x=8115.94
  now 8115.94*7/200=284
  and 8115.94*10/300=270
  so answer is 14 less he has to pay
• 10 years agoHelpfull: Yes(1) No(0)
• Water filled by 1st pipe in 1 hr=1/10
  Water filled by 2nd pipe in 1 hr=1/12
  Water emptied by 3rd pipe in 1 hr=1/20
  Resultant Water in 1 hr,if all pipes are operated simultaneously=(1/10+1/12+120)=1/15
  Therefore Tank could be filled full in =(1/(1/15))=15 hrs
• 10 years agoHelpfull: Yes(0) No(4)
• (1/10)+(1/12)-(1/20)=2/15
  in 1 hours
  and hence in 15/2=7.5 hours.
• 10 years agoHelpfull: Yes(0) No(0)
• net rate of filling tank = 1/10 + 1/12 - 1/20 = 2/15
  
  it takes 15/2 hours to fill the tank...
• 10 years agoHelpfull: Yes(0) No(0)
• work in one hr 1/10+1/12-1/20=8/60
  complete work in=60/8=7hr30min
• 10 years agoHelpfull: Yes(0) No(0)
• 7.5 hrs.capacity is 120 .1 hr (22-6)=16
• 10 years agoHelpfull: Yes(0) No(0)