A man drives a car a distance of 200km at an average speed of 44km/h.What must be his average speed for the next 220km if he is to cover the total distance in 9 hours?
To find the required average speed for the next 220 km, we can start by determining the time taken to cover the first part of the distance.
Given:
Distance covered in the first part = 200 km
Average speed of the first part = 44 km/h
To calculate the time taken for the first part, we can use the formula:
Time = Distance / Speed
So, for the first part:
Time taken for the first 200 km = 200 km / 44 km/h
Now, let's find out the remaining time available after covering the first part of the distance. We know that the total time available is 9 hours. Therefore, the remaining time is:
Remaining time = Total time available - Time taken for the first part
Remaining time = 9 hours - (200 km / 44 km/h)
Now, we can calculate the average speed needed for the next 220 km based on the remaining time:
Average speed for the next 220 km = 220 km / Remaining time
Substituting the values:
Average speed for the next 220 km = 220 km / (9 hours - [200 km / 44 km/h])
Simplifying the expression:
Average speed for the next 220 km = 220 km / (9 hours - 4.55 hours)
Average speed for the next 220 km = 220 km / 4.45 hours
Calculating the value:
Average speed for the next 220 km ≈ 49.44 km/h
Therefore, the man must maintain an average speed of approximately 49.44 km/h for the next 220 km in order to cover the total distance of 420 km in 9 hours.