# Quantitative Aptitude: Time and Work Set 12

Time and Work Questions for IBPS/SBI PO, NIACL, NICL, LIC, BOI, Bank of Baroda and other competitive exams

1. 20 Men can complete a work in 12 days and 24 Boys can complete same work in 20 days. 16 men and 8 boys started working and worked for 12 days. How many more days are needed to complete the work?
A) 4 days
B) 7 days
C) 9 days
D) 2 days
E) No more days needed.
Option E
Solution:

20M * 12 days = 24B *20 days
then 1M=2B
Now 16M + 8B==>16M+4M=12 days ie 20M=12 days.
So no more days needed to complete the work.
2. A and B each working alone can do a work in 12 and 36 days respectively. They started the work together but A left after sometime and B finished the remaining work in 4 days. After how many days from the start did A leave?
A) 10 days
B) 8 days
C) 12 days
D) 3 days
E) None
Option B
Solution:

A 12 3unit(A’s work)
B 36 1unit(B’s work) Both Lcm 36 (whole work)
B work 1 unit per day then for 4 days 4unit.
remaining 36-4=32 unit left that done by both A and B
Both work unit (3+1) 4 ==>32/4===>8days.
3. A man ‘A’ can do a piece of work in 10 days, man ‘B’ can do the same piece of work in 12 days while man ‘C’ can do it in 15 days. They started work together but after 2 days ‘A’ left the work and the remaining work was completed by ‘B’ and ‘C’ together. Find in how many days will the work be completed.
A) 5 days
B) 7 days
C) 2 1/6 days
D) 3 1/3 days
E) None of these
Option D
Solution:

A…..10                          6unit
B……12   Lcm=60      5unit
C…….15                       4unit
Work of all 3  per day is 15 units (6+5+4)
All 3 worked for 2 days. So 2 days work is 2*15=30units.
Remaining (60-30)=30unit
That work done by B and C their per day work unit (5+4)=9unit
Remaining work done by B and C is 30/9=3 1/3 days.
4. An empty tank whose capacity is 50 litres. There is an inlet pipe which fills at 7 L/min and there is an outlet pipe which empties at 6L/min. Both the pipes function alternately for 1 minute. The inlet pipe is the first one to function, how much time will it take for the tank to be filled up to its capacity?
A) 95
B) 100
C) 87
D) 110
E) none
Option C
Solution:

Capacity 50 litres
1st Minute 7l filled (through inlet pipe)
2nd minute 6l emptied(through outlet pipe)
In 2 minutes (7litres -6 litres =) 1l is filled
It takes 2 minutes to fill 1l then 84 minutes to fill 42 litres.
in 85th min – 42+7 = 49
in 86th – 49-6 = 43
in 87th – 43+7 = 50
5. There are three pipes, A, B and C, attached to container. A and B can fill the container alone in 20 and 30 mins, respectively whereas C can empty the container alone in 45 mins. The three pipes are kept opened alone for one minute each in the the order A, B and C. The same order is followed subsequently. In how many minutes will the reservoir be full?
A) 25 min
B) 35 min
C) 20 min
D) 47 min
E) None of these
Option D
Solution:

A……20                                            9unit (180/20)
B……30     180 (LCM)                   6unit
C……45                                            4unit
1st Minute => A is opened => fills 9 L
2nd Minute => B is opened =>fills another 6 L
3rd Minute => C is opened => empties 4 L
Hence every 3 minutes => (9 + 6 – 4 =) 11 litres are filled into the container.
So in 45 minutes (11 × 15 =) 165 litres are filled.
In the 46th minute A is opened and it fills 9 litres. In the 47th minute B is opened and it fills 6 litres.
Hence the container will be full in 47 minutes.
6. Efficiency of A is 50% more than B and B takes 21 days to complete a piece of work. A started the work alone and then B joined her 5 days before actual completion of the work. For how many days A worked alone?
A) 6 days
B) 4 1/2 days
C) 5 2/3 days
D) 7 days
E) None
Option C
Solution:

Efficiency (A : B) =150:100= 3 : 2 then days 2:3
B takes 21 days to do the work. Then A takes 14 days to do the work.
(3 === 21
2 ?=== 14 days.)
Now A…….14                         3unit
.        B…….21   Lcm 42         2unit
then B joined with A and worked for 5days ==>5*5(3+2) = 25 unit
remaining (42-25)=17unit
then A did that 17 unit alone is 17/3==5 2/3 days.
7. M can do a piece of work in 10 days working 10 hours a day. The work is started by M and on the second day one man whose capacity to do the work is twice that of M, joined. On the third day another man whose capacity is thrice that of M, joined and the process continues till the work is completed. In how many days will the work be completed, if everyone works for five hours a day?
A) 4
B) 6
C) 7
D) 3
E) None
Option A
Solution:

M total work 10*10=100
1st day =5hrs
2nd day =10+5=15
3rd day =15+10+5=30
4th day =20+15+10+5=50
Total (5+15+30+50) = 100
So 4th day they completed the work.
8. A tent can be built by a certain number of workers in 20 days. But it requires less than 20 workers to build it in 30 days. How many workers will build it in 50 days?
A) 30
B) 24
C) 50
D) 18
E) None
Option B
Solution:

Let, x workers can do the work in 20 days.
then no of workers require to finish it in 30 days is 20x / 30
20x/30 = (x – 20)
10x = 600
x = 60
So, No of workers require to finished it in 50 days = (60 * 20) / 50 = 24 workers.
9. A can do a particular work in 6 days . B can do the same work in 8 days. A and B signed to do it for Rs. 4000. They completed the work in 3 days with the help of C. How much is to be paid to C?
A) 380
B) 600
C) 500
D) 450
E) None
Option C
Solution:

A =6
B =8
.                 A                   B                  C                  A+B+C
Days         6                   8                  24                     3
.            (6*4)            (8*3)            (24*1)              (8*3)                 LCM 24
Units      4                    3             [8-(4+3] 1       8(total unit)
So C work 24 days to complete a work.
Then the ratio 1/6 : 1/8 : 1/24 = 4 : 3 : 1
Now total amount Rs4000 ie (ratio 4+3+1) 8 ==4000
.                                                                             1(C’s ratio)=? 4000/8*1=500Rs
Amount paid to C is Rs 500.
10. Ram and Ravi can separately do a piece of work in 20 and 15 days respectively. They worked together for 6 days, after which Ravi was replaced by Rohit. If the work was finished in next 4 days, then the number of days in which Rohit alone could do the work will be :
A) 40
B) 42
C) 45
D) 50
E) None
Option A
Solution:

Ram and Ravi worked together
1/20+1/15=(3+4)/60= 7/60
they work for 6 days so 7/60*6=7/10
Remaining work 3/10 done by Ram and Rohit.
Ram and Rohit finished in 4days so 3/40.
now 3/40-1/20=1/40

## 6 Thoughts to “Quantitative Aptitude: Time and Work Set 12”

1. naga pradeep

Ira can do a piece of work in 10 days, Nisha can do it in 15 days and Isha can do it 20 days. All three of them started the work together. However, Ira left after 2 days and Nisha left after 4 days. How long will Isha have to work for to complete the task?

1. arpita

work…………….60
Ira………………6
Nisha…………4
Isha…………..3

2(13) + 2( 7) + x(3) = 60
26+14+3x = 60 >> x = 20/3

1. naga pradeep

can you explain in detail please i mean step by step bcz i did not understand above procedure

1. arpita

ira worked for 2 days so 1/10 * 2 = 1/5
nisha – 1/15* 4
so 1/5 + 4/15 + 1/20 * x = 1
x = 32/3
so more days nisha work = 32/3 – 4 = 20/3

2. AmRITa @ bank po

mam in Q5-LCM is 180.so why cant we take 11*16

3. jaga

q7 ??

thank u mam