Trains Boats and Streams Practice Test 4 with solutions

Let the speed of the train be S km/hr and the distance travelled is D km.
Total time taken =

D

S

hrs
First Case:

150

S

+(

D−150

3S

)×5 =

D

S

+8
450 + 5D - 750 = 3D + 24S
2D - 24S = 750 - 450 = 300
2D - 24S = 300 ......(i)
Second Case:

510

S

+(

D−510

3S

)×5 =

D

S

+4
1,530 + 5D - 2,550 = 3D + 12S
2D - 12S = 2,550 -1,530 = 1,020 ……(ii)
From (i) and (ii) we get,
12S = 720
S = 60 km/hr.
⇒ 2D = 300 + 24S
= 300 + 24 × 60
2D = 1,740
D = 870 km