# Time Speed & Distance Questions for RRB Group-D PDF

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## Time Speed & Distance Questions for RRB Group-D PDF

Download Top-10 RRB Group-D Time Speed & Distance Questions PDF. RRB GROUP-D Time Speed & Distance  questions based on asked questions in previous exam papers very important for the Railway Group-D exam.

Question 1: A person travelling at a certain speed reaches his office 5 minutes late. On doubling the speed he reaches the office 5 minutes early. If he leaves the home at 7:30 a.m., when does his office start?

a) 8:00 a.m.

b) 7:55 a.m.

c) 7:45 a.m.

d) 7:50 a.m.

Question 2: Find the average speed of a car if it travels 10km with the speed of 15 km/hr and another 10km with the speed of 10km/hr?

a) 12km/hr

b) 15km/hr

c) 12.5km/hr

d) 14km/hr

Question 3: At what time between 1 and 2 does the hour hand and the minute hand meet?

a) 5 minutes after 1.

b) 60/11 minutes after 1.

c) 6 minutes after 1

d) 63/11 minutes after 1.

Question 4: Two trains of lengths 200 and 300 meters are running towards each other with the speeds of 36 km/h and 90 km/h. How long will they take to cross each other?

a) 90/7 sec.

b) 99/7 sec.

c) 100/7 sec.

d) 110/7 sec.

Question 5: If a person travelled the first 2 hours of the journey at 40kmph and the next 2 hours at 60kmph, find the average speed.

a) 45

b) 48

c) 50

d) 52

Question 6: A car and a bus are travelling from points A and B respectively with speeds 80kmph and 60kmph respectively. If the initial distance between them is 280km, find the distance from B at which they meet.

a) 160 km

b) 120 km

c) 100 km

d) 140 km

Question 7: Find the number of non-negative integral solutions of the equation x + y + z = 4

a) 10

b) 12

c) 15

d) 18

Question 8: What is the time taken for a 300 metre long train speeding at 60 kmph to cross a pole ?

a) 5 seconds

b) 30 seconds

c) 50 seconds

d) 18 seconds

Question 9: A man swim at 5 km per hour velocity in still water He takes 75 minutes to swim from position A to the position B and back in a river when it is flowing at 1 km per hour The distance between A and B is

a) 6 km

b) 5 km

c) 2.5 km

d) 3 km

Question 10: A farmer travelled a distance of 61 km. in a 9 hours. He travelled partly on foot at the rate of 4 km. per hour and partly on bicycle at the rate of 9 km. per hour. The distance travelled on foot is:

a) 17 km.

b) 16 km.

c) 15 km.

d) 14 km.

Let the office time be x minutes after 7:30.
In the first instance he takes x+5 minutes. In the second instance he takes x-5 minutes.
(x+5)/(x-5) = 2
2x-10 = x+5
x = 15 minutes
So the office time is 7:45 a.m.

When the distance travelled is same, then the average speed is the harmonic mean of the two speeds.
Avserage speed = (2*15*10)/(15+10) = 2*3*2 = 12 km/hr

At 1 o clock, the angle between the hour hand and the minute hand is 30 degrees.
Relative speed of minute hand with respect to hour hand = 11/2 degrees per minute.
Time taken by minute hand to meet hour hand =$\frac{30}{\frac{11}{2}}$= 60/11 minute.

Relative speed = (10+25) meter/second (36 km/h = 10 m/s and 90 km/h = 25 m/s.)
Total distance = 500 m
Time taken to cross each other = 500/35 = 100/7 sec.

Total distance travelled = 2*40 + 2*60 = 200 km
Total time = 2 + 2 = 4 hours
Average Speed = $\frac{200}{4}$ = 50 kmph

Let the distace from B be x km.
$\frac{280-x}{80}$ = $\frac{x}{60}$
=> (280*60) – 60x = 80x
=> 140x = 280 * 60
=> x = 120 km

If z=0, then x + y = 4 => (0,4),(1,3),(2,2),(3,1),(4,0) => 5
If z=1, then x + y = 3 => (0,3,),(1,2),(2,1),(3,0) => 4
If z=2, then x + y = 2 => (2,0),(1,1),(0,2) => 3
If z=3, then x + y = 1 => (0,1),(1,0) => 2
If z=4, then x + y = 0 => (0,0) => 1
=> 15 solutions.

Length of the train = 300 metres.

Speed = 60 kmph = 60 * 5/18 m/s

Time taken = length / speed = 300*18/60*5 = 18 seconds

Let the distance be x

Relative speed when travelling upstream = 5 – 1 = 4 kmph

Relative speed when travelling downstream = 5 + 1 = 6 kmph

Time taken = 75 minutes = 1.25 hours

So, x/4 + x/6 = 1.25

So, x = 3 kms