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Time & Work Questions for RRB Group-D PDF

Download Top 15 RRB Group-D Time & Work Questions and Answers PDF. RRB Group-D Time & Work questions based on asked questions in previous exam papers very important for the Railway Group-D exam.

Question 1:Â A person working 8 hours per day completed a piece of work in 9 days. If the work needs to be completed in 6 days, how many hours should he work per day?

a)Â 12 hours

b)Â 10 hours

c)Â 14 hours

d)Â 16 hours

Question 2:Â â€˜Pâ€™ can complete a work in 15 days. â€˜Qâ€™ 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)Â 30 days

b)Â 27 days

c)Â 21 days

d)Â 24 days

Question 3:Â A and B can do a piece of work individually in 12 hours and 20 hours respectively. They work on alternate hours starting with A. Then in how many hours, will the total work be completed?

a)Â 12 hr 48 min

b)Â 14 hr 48 min

c)Â 16 hr 36 min

d)Â 14 hr 36 min

Question 4:Â A,B and C can do a piece of work individually in 12,16 and 24 days respectively. They all started the work together but after 4 days, A and B left. Then, in how many days total work will be completed?

a)Â 4 days

b)Â 6 days

c)Â 10 days

d)Â 12 days

Question 5:Â Ravi started his journey from his house to office with 40 kmph speed, it took 2hrs for him to reach his office. Then find the time at which he reached his home if he travels at a speed of 30 kmph ?

a)Â $2\frac{3}{2}hrs$

b)Â $2\frac{2}{3}hrs$

c)Â $3\frac{2}{3}hrs$

d)Â $3\frac{3}{2}hrs$

Question 6:Â 2 men or 3 women can complete a work in 12 days, then in how many days can 3 men and 9 women complete the work ?

a)Â $2\frac{1}{3}$ days

b)Â $2\frac{2}{3}$ days

c)Â $3$ days

d)Â $3\frac{1}{3}$ days

Question 7:Â What is the time taken by a flight to cover 1875 km if it is moving at 500 kmph?

a)Â 3hrs 30mins

b)Â 3hrs 35mins

c)Â 3hrs 40mins

d)Â 3hrs 45mins

Question 8:Â 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)Â 32 seconds

b)Â 34 seconds

c)Â 36 seconds

d)Â 38 seconds

Question 9:Â Deepak and Gaurav can finish a piece of work in 24 days. Both of them started the work but Gaurav left after 10 days. Deepak completed the rest of the work in 28 days. How much time will Deepak take to complete the entire work alone?

a)Â 48 days

b)Â 60 days

c)Â 40 days

d)Â 54 days

Question 10:Â 12 men can do a piece of work in 10 days. How many men would be required to do the same work in 8 days ?

a)Â 14

b)Â 18

c)Â 16

d)Â 15

Question 11:Â What is the time at which hour hand and minute hand meet between 2 o clock and 3 o clock?

a)Â 10 minutes after 2

b)Â 120/11 minutes after 2

c)Â 117/11 minutes after 2

d)Â 15 minutes after 2

Question 12:Â Two trains of length 150m and 250m are travelling at the speed of 25m/s and 15m/s in the opposite direction. Find the time taken by the trains to cross each other completely.

a)Â 8 s

b)Â 14 s

c)Â 12 s

d)Â 10 s

Question 13:Â Sita and Gita can do a particular work in 20 days and 25 days respectively. Both Sita and Gita start working together and after 5 days Gita leaves. How many more days would Sita require to complete the work?

a)Â 11 days

b)Â 15 days

c)Â 20 days

d)Â 6 days

Question 14:Â Find the time taken by police to catch a thief if the thief is running at the speed of 30km/hr and the police is following him at the speed of 75km/hr and the initial distance between them is 200m.

a)Â 20 seconds

b)Â 12 seconds

c)Â 16 seconds

d)Â 8 seconds

Question 15:Â Ram and Shyam can do a work in 24 days. Shyam alone can do its 1/3 part in 12 days. How long will Ram take to complete the remaining work?

a)Â 24 days

b)Â 72 days

c)Â 48 days

d)Â 96 days

$\text{No. of hours}_1\times\text{No. of days}_1 = \text{No. of hours}_2\times\text{No. of days}_2$
Let the number of hours he should work per day be x
â‡’ $8\times9 = 6\times x$
â‡’ $x = 12$

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 60 units (LCM of 12 and 20)
Efficiency of A = 60/12 = 5 units/hr
Efficiency of B = 60/20 = 3 units/hr
They work on alternate days.
Then, A and B can do 8 units in 2 hours.
â‡’ 56 units of work will be completed in 14 hours.
Remaining work = 4 units
A can complete 5 units in 1 hour
Then, 4 units of work can be completed by A in 4/5th of an hour = $\dfrac{4}{5}\times60 = 48$ min
Therefore, Total work will be completed in 14 hours 48 min.

Let the total work be 48 units (LCM of 12,16 and 24).
Efficiency of A = 48/12 = 4 units/day
Efficiency of B = 48/16 = 3 units/day
Efficiency of C = 48/24 = 2 units/day
Then, Total work done by A,B,C in one day = 9 units
In 4 days, 36 units of work will be completed.
Remaining work = 48-36 = 12 units.
12 units will be completed by C in 12/2 = 6 days.
Therefore, Total work will be done in 4+6 = 10 days

Distance b/w his house & office = Speed*time = 40*2 = 80 km

In second case, his speed = 30 kmph

Time taken to reach his home = $Distance/speed = 80/30 = 8/3 = 2\frac{2}{3}hrs$

So the answer is option B.

2 men can complete the work in 12 days ==> so 1 man can do it in 12*2 = 24 days ==> efficiency of man = 1/24

3 women can complete the work in 12 days ==> so 1 woman can do it in 12*3 = 36 days ==> efficiency of man = 1/36

let 3 men and 9 women complete the work in x days, then

$\frac{1}{x} = 3(\frac{1}{24})+9(\frac{1}{36})$

==>Â $\frac{1}{x} = (\frac{1}{8})+(\frac{1}{4})$

==>Â $\frac{1}{x} = (\frac{1}{8})+9(\frac{2}{8})$

==> $\frac{1}{x} = \frac{3}{8}$

==> $x = 8/3 = 2\frac{2}{3}$ days

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.

Let us assume that Deepak alone can finish the work in â€˜xâ€™ days and Gaurav alone can finish it in â€˜yâ€™ days. So we have
$\frac{1}{x} + \frac{1}{y} = \frac{1}{24}$
Moreover
$\frac{38}{x} + \frac{10}{y} = 1$
=> Dividing this equation by 10, we get
$\frac{3.8}{x} + \frac{1}{y} = \frac{1}{10}$
Comparing the two equations, we get
$\frac{1}{10} – \frac{3.8}{x } = \frac{1}{24} – \frac{1}{x}$
=> $\frac{2.8}{x} = \frac{1}{10} – \frac{1}{24}$
=> x = 48
Hence, Deepak can finish the work alone in 48 days

12 men can do a work in 10 days

How many men are needed to complete the work in 8 days

= 12 x 10 / 8 = 15

At 2 o clock, the angle between the hour hand and minute hand is 60 degrees. This means that the relative distance between the two hands is 60 degrees.
Relative velocity of minute hand with respect to hour hand = 11/2 degrees per minute.
Time taken by minute hand to cover the gap of 60 degrees =$\frac{60}{\frac{11}{2}} =\frac{120}{11}$ minutes.

Sum of the Length of the trains = 150m + 250m = 400m. Hence, the trains have to cover 400m to completely cross each other.
As they are moving in opposite directions, we add their velocities. Hence, Relative velocities = 25+15 = 40m/s
Time taken = 400/40 = 10s

Sita and Gita 5 days work = 5(1/20 + 1/25) = 9/20
Remaining work = 1 – 9/20 = 11/20
Sita will complete 11/20 work in $\frac{\frac{11}{20}}{\frac{1}{20}}$ = 11 days.

Initial distance = 200m
Relative speed = 75-30 km/hr = 45km/hr = 12.5m/s
Time = 200/12.5 = 16s