Model 3 Opening both taps and leaks Section-Wise Topic Notes With Detailed Explanation And Example Questions
MOST IMPORTANT quantitative aptitude - 3 EXERCISES
The following question based on pipes & cisterns topic of quantitative aptitude
(a) 24
(b) 36
(c) 30
(d) 12
The correct answers to the above question in:
Answer: (a)
Using Rule 1 and 2,
Part of tank filled by pipes A and B in 1 minute
= $1/30 + 1/45 = {3 + 2}/90 = 1/18$ part
Part of tank filled in 12 minutes
= $12/18 = 2/3$ part
Remaining part
= $1 - 2/3 = 1/3$ part
When pipe C is opened,
Part of tank filled by all three pipes
= $1/30 + 1/45 - 1/36$
= ${6 + 4 - 5}/180 = 5/180 = 1/36$
Time taken in filling $1/3$ part
= $1/3$ × 36 = 12 minutes
Total time = 12 + 12 = 24 miuntes
Discuss Form
Read more opening both taps and leaks Based Quantitative Aptitude Questions and Answers
Question : 1
An empty tank can be filled by pipe A in 4 hours and by pipe B in 6 hours. If the two pipes are opened for 1 hour each alternately with first opening pipe A, then the tank will be filled in
a) 5$1/2$ hours
b) 4$2/3$ hours
c) 1$3/4$ hours
d) 2$3/5$ hours
Answer »Answer: (b)
Part of the tank filled in first 2 hours
= $1/4 + 1/6 = {3 + 2}/12 = 5/12$ Part
Part of the tank filled in first 4 hours
= ${2 × 5}/12$ parts= $5/6$ parts
Remaining part = $1 - 5/6 = 1/6$
Now it is the turn of pipe A
Time taken to fill $1/4$ part = 1 hour
Time taken to fill $1/6$ part
= $1/6 × 4 = 2/3$ hour
Total time = 4 + $2/3 = 4{2}/3$ hours
Question : 2
Three pipes A, B and C can fill a tank in 6 hours. After working together for 2 hours, C is closed and A and B fill the tank in 8 hours. The time (in hours) in which the tank can be filled by pipe C alone is
a) 9
b) 8
c) 10
d) 12
Answer »Answer: (d)
Part of the tank filled by
(A + B + C) in 1 hour = $1/6$
Part of tank filled by these in 2 hours
= $2/6 = 1/3$
Remaining part = $1 - 1/3 = 2/3$
Time taken by A and B in filling
$2/3$ rd part = 8 hours
Time taken by A and B in filling the whole tank
= ${8 × 3}/2$ = 12 hours
Part of tank filled by C in an hour
= $1/6 - 1/12 = 1/12$
Hence, required time = 12 hours
Question : 3
A tap can fill a tank in 6 hours. After half the tank is filled, three more similar taps are opened. What is the total time taken to fill the tank completely ?
a) 3 hours 45 minutes
b) 3 hours 15 minutes
c) 4 hours
d) 4 hours 15 minutes
Answer »Answer: (a)
A tap can fill the tank in 6 hours. In filling the tank to its half, time required = 3 hours.
Remaining part = $1/2$
Since, 1 tap takes 6 hours to fill the tank
Time taken by 4 taps take to fill $1/2$ of the tank
= $6/4 × 1/2 = 3/4$ hour
Total time = $3 + 3/4$
= $3{3}/4$ hours = 3 hours 45 minutes
Question : 4
A tank has two pipes. The first pipe can fill it in 4 hours and the second can empty it in 16 hours. If two pipes be opened together at a time, then the tank will be filled in
a) 5$1/3$ hours
b) 6 hours
c) 5$1/2$ hours
d) 10 hours
Answer »Answer: (a)
Using Rule 7,
Part of tank filled by both the pipes in 1 hour
= $1/4 - 1/16 = {4 - 1}/16 = 3/16$
Required time = $16/3 = 5{1}/3$ hours
Question : 5
Two pipes A and B can fill a cistern in 37$1/2$ minutes and 45 minutes respectively. Both pipes are opened. The cistern will be filled just in half an hour, if the pipe B is turned off after :
a) 9 minutes
b) 5 minutes
c) 15 minutes
d) 10 minutes
Answer »Answer: (a)
Pipe A fills the tank in $75/2$ minutes.
Part of the tank filled by A in 30 minutes
= $2/75 × 30 = 4/5$
Remaining part
= $1- 4/5 = 1/5$
Now, 1 part is filled by pipe B in 45 minutes
$1/5$ part is filled in
= 45 × $1/5$ = 9 minutes
Hence, the pipe B should be turned off after 9 minutes.
Question : 6
A tap takes 36 hours extra to fill a tank due to a leakage equivalent to half of its inflow. The inflow can fill the tank in how many hours ?
a) 18 hrs
b) 30 hrs
c) 36 hrs
d) 24 hrs
Answer »Answer: (a)
Using Rule 7,
Let the inflow fill the tank in x hours.
$1/x - 1/{2x} = 1/36$
[leakage being half of inflow]
= ${2 - 1}/{2x} = 1/36$
2x = 36
$x = 36/2$ = 18 hours
GET pipes & cisterns PRACTICE TEST EXERCISES
Model 1 Basic Pipes & Cisterns problems
Model 2 Filling tank by parts or fractions
Model 3 Opening both taps and leaks
pipes & cisterns Shortcuts and Techniques with Examples
Verbal Reasoning
Question & Answer Quiz
Non Verbal Reasoning
Question & Answer Quiz
Quantitative Aptitude
Question & Answer Quiz
Computer MCQ
Question & Answer Quiz
General English
Question & Answer Quiz
History GK
Question & Answer Quiz
Polity GK
Question & Answer Quiz
Geography GK
Question & Answer Quiz
Economy GK
Question & Answer Quiz
General Awareness GK
Question & Answer Quiz
Recently Added Subject & Categories For All Competitive Exams
Syllogism Practice Questions Answers PDF - IBPS Clerk 2024
Practice Verbal Reasoning Syllogism multiple choice questions and answers with Fully solved explanation, PDF for the IBPS Clerk Prelims 2024 Bank Exam
Continue Reading »
IBPS Clerk Prelims 2024 Synonyms Questions Solved Answers
Most important IBPS Clerk Prelims 2024 Synonyms and Antonyms multiple choice questions and answers with detailed solutions, English vocabulary PDF Download
Continue Reading »
New Cloze Test Questions and Answers PDF - IBPS Clerk 2024
The most important Cloze Test questions with detailed answers for upcoming IBPS Clerk prelims 2024. Latest English verbal ability practice MCQs, PDF
Continue Reading »
Mensuration Aptitude Practice Mcq Questions IBPS Clerk 2024
Most Important Practice Mensuration aptitude multiple choice questions, answers with detailed solutions, PDF beginner to advanced for IBPS Clerk Prelims 2024
Continue Reading »