Answer:
the least required speed is 103.88 km/h
Step-by-step explanation:
Data provided in the question:
Total distance = 270 km
Total time to reach = Time between 8 a.m and 11:15 a.m i.e 3.25 hours
Now,
For the distance of 110 km speed was 100 km/h
therefore, the time taken to cover 110 km = [tex]\frac{\textup{Distance}}{\textup{speed}}[/tex]
= [tex]\frac{\textup{110 km}}{\textup{100 km/h}}[/tex]
= 1.1 hour
For another 43 km speed was 42 km/h
therefore, the time taken to cover 43 km = [tex]\frac{\textup{Distance}}{\textup{speed}}[/tex]
= [tex]\frac{\textup{43 km}}{\textup{42 km/h}}[/tex]
= 1.0238 hours
Now,
The distance left to be covered = 270 - 110 - 43 = 117 km
Time left = 3.25 h - 1.1 h - 1.0238 h = 1.1262 h
Thus required speed = [tex]\frac{\textup{117 km}}{\textup{1.1262 h}}[/tex]
= 103.88 km/h
Hence, the least required speed is 103.88 km/h
