Mathews usually makes the 100 km journey to visit his family. The trip involves three separate stages:

a) A stage of 20 km that is travelled on small roads at a constant speed of 30 km/h.

b) A stage of 50 km that is travelled on the highway at a constant speed of 100 km/h.

c) A stage of 30 km that is travelled on standard roads at a constant speed of 40 km/h.

1 - How long does it normally take Mathews to make this journey?

Last week there were roadworks on a section of the highway, and he was only able to travel at 60 km/h for the length of the roadworks. Matthews's journey last week took 6 minutes longer than usual.

2 - What was the length of the section of roadworks?

1. Total time = 1 hr 55 minutes

2 Distance = 121 km

Step-by-step explanation:

Mattew journey

stage a

Distance = 20km

Speed = 30km/h

Time = distance/speed

Time = 20/30

Time = 2/3 h

Time = 40 minutes

Stage b

Distance = 50 I'm

Speed = 100 km/h

Time = distance/speed

Time = 50/100

Time = 0.5 h

Time = 30 minutes

Stage c

Distance = 30 km

Speed = 40 km/h

Time = distance/speed

Time = 30/40

Time = 3/4 h

Time = 45 minutes.

Total time taken = (40 + 30 + 45) minutes

Total time = 115 minutes

Total time = 1 hr 55 minutes

2.

Speed = 60 km/h

Time = 6 minutes + x

And x = 1 hr 55 minutes

Time = 1 hr 55 minutes + 6 minutes

Time = 2 hr 1 minute

Time = 2.01666667 hr

Distance covered = speed * time

Distance = 60*2.016667

Distance = 121 km