A and B can fill a cistern in 15/2 min and 5 min and C can carry of 14 litres per minute. If all pipes are open when it is full , it is emptied in 1 hours. How many litres can it hold?

• Let tank hold v litres
  => rate of A : v/(15/2) = 2v/15
  => rate of B : v/15
  and rate of C: 14
  
  since the tank is emptied in one hour, total time : 1hr
  => water carried by C : 60*14 = 840
  
  and since
  full tank + water supplied by A + water supplies by B = water drained by C
  
  we have
  v + 60*(2v/15) + 60*(v/5) = 840
  => 21v = 840
  
  Therefore, v = 40 Litres
  
• 10 years agoHelpfull: Yes(33) No(0)
• 40 ltrs.
  tank holds x ltrs
  emptied in 1min
  14- 2x/15 + x/5 = (42-x)/3 ltrs
  now acc to qstn (42-x)/3 *60 =x
  so, x=40
• 10 years agoHelpfull: Yes(19) No(3)
• (y/1.5)=60////7.5+5-14=1.5
  y=90 litre
• 10 years agoHelpfull: Yes(3) No(2)
• 120 ltrs
  tank holds x ltrs
  in 1 h it becomes empty so
  x+(2x/15+x/5)*60-14*60=0
  x+20x-14*60=0
  x=40
  
• 10 years agoHelpfull: Yes(3) No(1)
• C's 1 min work =1/12
  c will take total 12 min .
  now, 1 min =14 litres .
  12 min =168 litres.
  
• 10 years agoHelpfull: Yes(0) No(8)
• 7.5+5 / 7.5*5
  125/75*5 = 1/3 *60 = 20
  20+1 = 21
  14*60/21 = 40
• 8 years agoHelpfull: Yes(0) No(0)