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# Time & Work Questions For RRB JE PDF

Download Top 20 RRB JE Time & Work Questions and Answers PDF. RRB JE Maths questions based on asked questions in previous exam papers very important for the Railway JE exam

Question 1: 84 men can do a piece of work in 16 days. If the work needs to be completed in 12 days, then how many more men are required?

a) 24

b) 28

c) 32

d) 16

Question 2: ‘P’ can complete a work in 15 days. ‘Q’ can complete the same work in 45 days.If they want to complete the work by working 3 days each alternatively starting with P then how many days does it take to complete whole work

a) 30 days

b) 27 days

c) 21 days

d) 24 days

Question 3: A and B can do a piece of work individually in 9 days and 15 days respectively. They work on alternate days starting with A. Then in how many days, the work will be completed?

a) 12 days

b) 9 days

c) 11 days

d) 8 days

Question 4: A and B can do a piece of work individually in 24 days and 16 days respectively. They both started the work together and after 3 days, C with double the efficiency of B joined. Then in how many days, will the work be completed?

a) 3 days

b) 6 days

c) 7 days

d) 4 days

Question 5: 5 men and 2 women can complete a work in 3 days. 2 man and 3 women can complete the work in 4 days. In how many days can 12 women finish the work ?

a) 13/7 days

b) 9/7 days

c) 11/7 days

d) 10/7 days

Question 6: A and B can do a piece of work individually in 12 days and 15 days respectively. They both started the work together but after 4 days, A left. Then in how many days will the total work be completed?

a) 10 days

b) 6 days

c) 8 days

d) 4 days

Question 7: P can do a work in 50 days, Q can do the same work in 100 days and after working for 20 days, C joins the work and after 10 days work has been completed. How many does C alone take to complete the work ?

a) 100

b) 70

c) 125

d) 50

Question 8: P can do a work in 10 days, Q can do the same work in 20 days and after working for 2 days, C joins the work and after 2 days work has been completed. How many days does C alone take to complete the work ?

a) 4

b) 3

c) 5

d) 6

Question 9: ‘A’ can do a piece of work in 6 days and ‘B’ can do it in 5 days if B joins with A after 2 days then in how many days will the work get completed ?

a) 42/11 days

b) 41/11 days

c) 40/11 days

d) 39/11 days

Question 10: A and B can do a piece of work individually in 14 hours and 21 hours respectively. A started the work and will be assisted by B on every alternate hour. Then find the time in which the total work will be completed?

a) 10 hours 40 minutes

b) 12 hours 20 minutes

c) 11 hours 24 minutes

d) 14 hours 40 minutes

Question 11: Find the time taken by 200m long train, travelling at 81 kmph to cross a man travelling at 9 kmph in the same direction ?

a) 15 sec

b) 10 sec

c) 20 sec

d) 25 sec

Question 12: What is the time taken by a flight to cover 1875 km if it is moving at 500 kmph?

a) 3hrs 30mins

b) 3hrs 35mins

c) 3hrs 40mins

d) 3hrs 45mins

Question 13: Train A of length 300m and Train B of length 600m are travelling with 35kmph and 55kmph respectively. Find the time taken by them to cross each other if they are moving in opposite direction ?

a) 32 seconds

b) 34 seconds

c) 36 seconds

d) 38 seconds

Question 14: A car leaves place A at 10 am and travels at 40 km/hr. A bus leaves place A at 12 am and travels at 60 km/hr along the same route as A. A biker leaves A at a certain time and overtakes both the car and the bus at the same time. If the biker travels at 120 km/hr then find the time at which biker left A.

a) 1 pm

b) 2 pm

c) 2:30 pm

d) 1:45 pm

Question 15: A boat can travel 27 km in one hour in still water and travels the same distance against the stream in 90 minutes. How much time will the boat take to travel 90 km in the direction of the stream?

a) 4 hours

b) 4.25 hours

c) 2.5 hours

d) 3.5 hours

Question 16: Balu travels from his home to office on his bike. After travelling 75% of the total distance, his bike develops a snag and hence, his speed gets reduced to a third of his original speed. He reaches office 30 minutes late. What is the usual time that Balu takes to travel from his home to the office?

a) 1 hour

b) 1.5 hours

c) 2 hour

d) 2.5 hours

Question 17: A train crosses a platform twice its length in 12 seconds. How much time will it take to cross a stationary pole?

a) 3 seconds

b) 4 seconds

c) 2 seconds

d) 6 seconds

Question 18: A boat goes at a speed of 30 kmph in still water. What time does it take to travel 50 kms upstream and then 70 kms downstream in water of speed 5 kmph?

a) 2 hours

b) 4 hours

c) 6 hours

d) 8 hours

Question 19: The speed of a car, excluding stoppages, is 80 kmph. Including stoppages, the speed of the car is 50kmph. For how many minutes does the car stop per hour?

a) 15

b) 22.5

c) 30

d) 37.5

Question 20: What is the time taken by P and Q to meet for the first time on the circular track of length 500m if they are travelling in the same direction and the speed of P is 90m/s and the speed of Q is 40m/s?

a) 10s

b) 12s

c) 8s

d) 5s

$\text No. of men_1 \times \text No. of days _2 = \text No. of men_2 \times \text No. of days_2$
Let the number of men required to complete the work in 12 days be ‘x’
=> $84\times16 = 12\times x$
=> $x = 112$
Therefore, Number of extra men required $= 112-84 = 28$.

LCM of 15 and 45 is 45. Total units of work=45
P can do 45/15 =3 units per day
Q can do 15/15=1 units per day
So starting with P we have 9+3+9+3+9+3+9=45
So total it takes 9*3=21 days

Let the total work be 45 units (LCM of 9 and 15)
Efficiency of A = 45/9 = 5 units/day
Efficiency of B = 45/15 = 3 units/day
They work on alternate days starting with A.
Then, 8 units of work will be completed in 2 days.
⇒ 40 units of work will be completed in 10 days.
Remaining work = 5 units.
5 units of work will be completed by A in 1 day.
Hence, Total work will be completed in 11 days.

Let the total work be 48 units (LCM of 24 and 16).
Efficiency of A = 48/24 = 2 units/day
Efficiency of B = 48/16 = 3 units/day
Then, 5 units of work will be completed in a day.
15 units of work will be completed in 3 days.
Now C joined with double the efficiency of B
⇒ Efficiency of C = 3*2 = 6 units/day
Remaining work = 33 units
33 units will be completed by A,B and C in 33/11 = 3 days.

Given (5*3)MD+(2*3)WD=total work
(2*4)MD+(3*4)WD=total work
15MD+6WD=8MD+12WD
7MD=(6)WD
Total work in terms of women days is
8(6/7)WD+12WD=(48+84)/7 WD
Total work=132/7 WD
Therefore 12*x=132/7
x=11/7 days

Let the total work be 60 units (LCM of 12 and 15)
Efficiency of A = 60/12 = 5 units/day
Efficiency of B = 60/15 = 4 units/day
Hence, in 1 day, 9 units of work will be completed.
⇒ In 4 days, 36 units of work will be completed.
Remaining work = 60-36 = 24 units.
24 units needs to be completed by B.
4 units will be completed by B in 1 day
24 units will be completed by B in 6 days.
Hence, Total work will be completed in 6+4 = 10 days.

LCM of 50 and 100 is 100 and so total 100 units of work has to be done.
Each day P can do 2 units of work
Each day Q can do 1 unit of work
After 20 days 60 units of work is done so 40 units is left
Given in next 10 days work has been completed along with C.
So 10(1+2+x)=40
3+x=4
x=1
C does 1 unit of work each day and so it takes 100 days for him to complete the whole work.

LCM of 10 and 20 is 20 and so total units of work has to be done.
Each day P can do 2 units of work
Each day Q can do 1 unit of work
After 2 days 6 units of work is done so 14 units is left
Given in next 2 days work has been completed along with C.
So 2(1+2+x)=14
3+x=7
x=4
C does 4 units of work each day and so it takes 5 days for him to complete the whole work.

LCM of 6 and 5 is 30 and so 30 units is the total work.
On each day A does (30/6)=5 units of work
On each day B does (30/5)=6 units of work
So in first 2 days A completes 10 units of work.
So 20 units of work has to be done by both and each day they can do 11 units of work.
So in $1\frac{9}{11}$ days remaining work will be completed
Total time taken is 2+$1\frac{9}{11}$=42/11 days

Let the total work be 42 units (LCM of 14 and 21)
Efficiency of A = 42/14 = 3 units/hour
Efficiency of B = 42/21 = 2 units/hour
A is assisted by B on every alternate hour
A can complete 3 units of work in first hour
A and B can complete 5 units of work in second hour.
Hence, 8 units of work will be completed in 2 hours.
Then, 40 units of work will be completed in 10 hours.
Remaining work = 2 units.
A can do 2 units of work in 2/3rd of an hour = $\dfrac{2}{3}\times60 = 40$ minutes
Therefore, Total work will be completed in 10 hours 40 minutes.

Relative speed = 81-9 = 72 kmph = 72*(5/18) = 20 m/s

Time = distance/speed = 200/20 = 10 sec

So the answer is option B.

Time = $\frac{distance}{speed} = \frac{1875}{500} = 3\frac{3}{4}hrs = 3hrs.45mins$

So the answer is option D.

relative speed = 35+55 = 90 kmph = 90*(5/18) = 25 m/s

Time taken to cross each other = $\frac{300+600}{25} = 36 seconds$

So the answer is option C.

The bus starts 2 hours after the car. Hence, the car would have covered 80 km in the mean time. Now relative speed of the car and the bus is 20 km/hr. Hence, bus will take 4 hours to reach the same point as the car. Hence, the distance travelled by the bus will be 60*4 = 240 km.
The biker will need 240/120 = 2 hours.
Thus, the biker must have started at 2 pm.

Let ‘s’ be the speed of the boat and ‘w’ be the speed of the stream.
We have, s = 27 km/hr and $\frac{27}{s-w} = 1.5$ hour
So s – w = 18 so w = 9 km/hr
We get, $\frac{90}{18+9} = 2.5$ hour
Hence, option C is the right choice.

The difference between the time taken to travel one-fourth of the total distance at reduced speed and normal speed is 30 minutes.
Let us consider the distance for which the bike travels at the reduced speed to be ‘d’.
=> Total distance = 4d.
Let the normal speed of the bike be ‘s’. => Reduced speed = s/3.

Now, we know that,
d/(s/3) – d/s = 30
(3d-d)/s = 30
2d/s = 30
=>d/s = 15 minutes.
Time taken to travel the distance between Balu’s home and office = 4d/s = 4*15 = 1 hour.
Hence, option A is the right answer.

Let us assume the length of the train to be ‘x’.
The total distance that the train has to travel to cross a platform of length ‘2x’ =sum of the lengths of train and platform.
Distance travelled = x+2x = 3x.
Speed of the train = 3x/12 = x/4.
The time the train will take to cross a stationary pole = x/(x/4) = 4 seconds.
Hence, option B is the right answer.

The relative speed of the boat in upstream = 30 – 5 = 25 kmph
Distance = 50 kms
Time = 50 / 25 = 2 hours.

Relative speed in downstream = 30 + 5 = 35 kmph
Distance = 70 kms
Time = 70/35 = 2 hours.

Total time = 2 + 2 = 4 hours.

Time taken to cover 30km = $\frac{30}{80}$ = 0.375 hours = 0.375 * 60 minutes = 22.5 minutes
As discussed in the concept time taken =$\frac{2\pi r}{x-y}$
$2\pi r = 500$
Time taken =$\frac{500}{90-40} = 10$s