Robert Bosch Time, Speed, and Distance Quiz 4

The relative speed of the boys = 16 kmph – 14 kmph
= 2 kmph

Distance between them is 10 km
Time = Distance/Speed
Time= 10km / 2 kmph = 5 hrs

In 1hr, the bus covers 60 km without stoppages and 40 km with stoppages.

Stoppage time = time takes to travel (100 - 60) km
i.e 40 km at 100 km/hr.
stoppage time = 40/60 hrs = 40 min.

Speed when he travels from Delhi to Patna = 80
Speed on return trip = 175% of 80 = 140 km/hr.
Average speed = (2 x 80 x 140)/(80 + 140) = 101.82 km/hr. ~ 102 km/hr

Initial speed = 120km/hr
Total distance = 120 x 8 = 960 km
New speed = 960/2 =480km/hr
Increase in speed = 480 - 120 = 360 km/hr

Let the time taken by train be 't' hrs.
Then,
50t = 25(t + 10/60)
40t = 35t + 25/6
5t = 5/6 hrs
Therefore, the Required length of the total journey d = s x t
= 40 x 5/6
= 100/3 km

As we know Speed = Distance / Time
for average speed = Total Distance / Total Time Taken
Thus, Total Distance = 328 + 512 = 840 km
Thus, Total Speed = 8
Average Speed = 840/8 => 105 kmph.

The first Autorikshaw covers 160 km in 5 hrs
=> Speed = 160/5 = 32 kmph
Now the second Autorikshaw covers the same distance in 1 hour less than the first = 4 hrs
=> Speed of the second train = 160/4 = 40 kmph
Now, the required difference in distance in 1 hour = 40 - 32 = 8 km.

Given that,
1st train speed = 80 km/hr
2nd train speed = 44 km/hr
Hence,
the relative speed of the two trains is 80 - 44 = 36 km/hr = 36 x 5/18 = 10 m/s
Therefore, the first train crosses the second train i.e (105 +205)m of distance with a speed of 10m/s.
Hence, (105 +205)/10 = 31 secs

Let 'd' be the distance between M and N
Spider man’s time = d/10 + d/9 = 19d/90 hours
Ant man’s time = 2d/12 = d/6 hours
We know that, 10 min = 1/6 hours
Thus, the time difference between M and N is given as 10 minutes.
=> 19d/90 - d/6 = 1/6
=> (19d-15d)/90 = 1/6
=> 4d/90 = 1/6
Thus,
d= 15/4 km = 3.75 km.
hence the distance between M and N is 3.75 km.

let 't' be the time after which they met since Chris Evans starts.
Given Robert Downey Jr is 100% faster than Chris Evans
40 t + 1.5*100(t-1) = 230
190t - 150 = 230
t = 380 / 190 = 2 hrs past the time that Chris Evans starts
So they meet at (10 + 3)hrs = 1:00 noon.