"Do not wait for leaders; do it alone, person to person."
- Mother Teresa
2.
Pipes A and B can fill a tank in 5 and 6 hours respectively. Pipe C can empty it in 12 hours. If all the three pipes are opened together, then the tank will be filled in:
Here pipes A and B are used for filling the tanks,
A and B takes 5 and 6 hours respectively to fill the tank .
for 1 hour ,A can fill 1/5th of the tank and B can fill 1/6th of the tank.
now tank C is used foe emptying the tank(water is running off from the tank)..it can empty the tank in 12 hours..means for 1 hour it empties 1/12th of water from the tank
NOTE:
A and B are filling the tank whereas C is used for emptying the tank.
therefore add A and B and subtract it from c
now consider how much water gets filled in the tank in 1 hour,
1/5+1/6-1/12=17/60
for 1 hour----17/60
? hours----1
(note: for 1 hour-- 17 parts got filled up out of 60 parts
for "?"hours-- 60 parts get filled up out of 60 (60/60=1)
Here 1 indicates tank gets filled)
just by cross multiplying it
(1*1)=(?*17/60)
?=(17/60)/(1*1)
60/17 hours it can fill the tank.
Hi guys use this concepts to find the solution in easily
Concept 1:
A fill tank in x hrs and B fill in Y hrs and C in z hrs means together fill=?
A&B=X*y/x+y
let that A&B ans as p
then A,B&C=p*z/p+z
Concept 2:
A fill tank in x hrs and B empty in Y hrs then both together work how much time is to empty=?
=x*y/y-x
Rav said:
(Thu, Feb 16, 2012 12:58:14 AM)
Will it work in every case ?
Divya said:
(Sun, Feb 26, 2012 05:37:58 PM)
Thanks manasa.
Mageswari said:
(Sun, Jul 29, 2012 11:26:23 AM)
Thanks manasa your explanation is clear cut.
Rohit said:
(Mon, Aug 27, 2012 07:31:06 PM)
Thanks neha.
Kiran said:
(Fri, Oct 12, 2012 11:07:30 PM)
@kaveri
1/5+1/6+-1/12=
L.C.M of 5,6,12=60
So 1/5+1/6-1/12
12+10-5
--------------= 17
60 --------
60
Alka said:
(Wed, Oct 17, 2012 12:12:57 PM)
@Happy.
First of all take L.C.M of 5, 6, &12. Then divide this L.C.M with every numerator & multiply that value with denominator of same.
The tank will be full in