Pipes & Cisterns - Question A Day - CAT 2008
April 08, 2002 � A tank is fitted with 8 pipes, some
of them that fill the tank and others that are waste pipe meant to empty the
tank. Each of the pipes that fill the tank can fill it in 8 hours, while each of
those that empty the tank can empty it in 6 hours. If all the pipes are kept
open when the tank is full, it will take exactly 6 hours for the tank to empty.
How many of these are fill pipes?
Solution �
April 15, 2002 � If A and B work together, they will complete a job in
7.5 days. However, if A works alone and completes half the job and then B takes
over and completes the remaining half alone, they will be able to complete the
job in 20 days.How long will B alone take to do the job if A is more efficient
than B?
Solution �
April 25, 2002 � Working together, A and B can do a job in 6 days. B and
C can do the same job in 10 days, while C and A can do it in 7.5 days. How long
will it take if all A, B and C work together to complete the job?
Solution �
May 23, 2002 � Pipe A fills a tank of 700 li class="text"tres capacity at the rate of
40 li class="text"tres a minute. Another pipe B fills the same tank at the rate of 30 li class="text"tres
a minute. A pipe at the bottom of the tank drains the tank at the rate of 20
li class="text"tres a minute. If pipe A is kept open for a minute and then closed and pipe B
is kept open for a minute and then closed and then pipe C is kept open for a
minute and then closed and the cycle repeated, how long will it take for the
empty tank to overflow?
Solution �
May 27, 2002 � There are 12 pipes that are connected to a tank. Some of
them are fill pipes and the others are drain pipes. Each of the fill pipes can
fill the tank in 8 hours and each of the drain pipes can drain the tank
completely in 6 hours. If all the fill pipes and drain pipes are kept open, an
empty tank gets filled in 24 hours. How many of the 12 pipes are fill pipes?
Solution �
June 06, 2002 � Four men and three women can do a job in 6 days. When
five men and six women work on the same job, the work gets completed in 4 days.
How long will a woman take to do the job, if she works alone on it?
Solution �
June 17, 2002 � A pump can be used either to fill or to empty a tank.
The capacity of the tank is 3600 m3. The emptying capacity of the
pump is 10 m3/min higher than its filli class="text"ng capacity. What is the
emptying capacity of the pump if the pump needs 12 more minutes to fill the tank
than to empty it?
Solution �
June 19, 2002 � Shyam can do a job in 20 days, Ram in 30 days and
Singhal in 60 days. If Shyam is helped by Ram and Singhal every 3rd
day, how long will it take for them to complete the job?
Solution �
July 29, 2002 � Pipe A usually fills a tank in 2 hours. On account of a
leak at the bottom of the tank, it takes pipe A 30 more minutes to fill the
tank. How long will the leak take to empty a full tank if pipe A is shut?
Solution �
August 01, 2002 � There are 12 pipes attached to a tank. Some of them
are fill pipes and some are drain pipes. Each of the fill pipes can fill the
tank in 12 hours, while each of the drain pipes will take 24 hours to drain a
full tank completely. If all the pipes are kept open when the tank was empty, it
takes 2 hours for the tank to overflow. How many of these pipes are drain pipes?
Solution �
September 27, 2002 � Two workers A and B manufactured a batch of
identical parts. A worked for 2 hours and B worked for 5 hours and they did half
the job. Then they worked together for another 3 hours and they had to do
(1/20)th of the job. How much time does B take to complete the job, if he worked
alone?
Solution �
October 10, 2002 � Pipe A can fill a tank in 'a' hours. On account of a
leak at the bottom of the tank it takes thrice as long to fill the tank. How
long will the leak at the bottom of the tank take to empty a full tank, when
pipe A is kept closed?
Solution �
October 16, 2002 � A and B working together can finish a job in T days.
If A works alone and completes the job, he will take T + 5 days. If B works
alone and completes the same job, he will take T + 45 days. What is T?
Solution �
March 13, 2003 � A man can do a piece of work in 60 hours. If he takes
his son with him and both work together then the work is finished in 40 hours.
How long will the son take to do the same job, if he worked alone on the job?
Solution �
May 15, 2003 � A, B and C can do a work in 5 days, 10 days and 15 days
respectively. They started together to do the work but after 2 days A and B
left. C did the remaining work (in days).
Solution �
June 13, 2003 � X alone can do a piece of work in 15 days and Y alone
can do it in 10 days. X and Y undertook to do it for Rs. 720. With the help of Z
they finished it in 5 days. How much is paid to Z?
Solution �
June 27, 2003 � Ram starts working on a job and works on it for 12 days
and completes 40% of the work. To help him complete the work, he employs Ravi
and together they work for another 12 days and the work gets completed. How much
more efficient is Ram than Ravi?
Solution �
August 08, 2003 � A red li class="text"ght flashes 3 times per minute and a green
li class="text"ght flashes 5 times in two minutes at regular intervals. If both li class="text"ghts start
flashing at the same time, how many times do they flash together in each hour?Solution
�
October 23, 2003 � A and B can do a piece of work in 21 and 24 days
respectively. They started the work together and after some days A leaves the
work and B completes the remaining work in 9 days. After how many days did A
leave?
Solution �
June 15, 2004 : Ram, who is half as efficient as Krish, will take 24 days
to complete a work if he worked alone. If Ram and Krish worked together, how
long will they take to complete the work?
Solution �
July 5, 2004 : A can complete a project in 20 days and B can complete the
same project in 30 days. If A and B start working on the project together and A
quits 10 days before the project is completed, in how many days will the project
be completed?
Solution �
