A motorist has to travel 3.50 km in a city with an average speed not exceeding 25 km/h. If the average speed increases to 40 km/h, fine the time he will gain in his journey
See previous post: Thu, 11-7-14, 6:30 AM.
To find the time gained in the journey, we need to calculate the time taken to travel 3.50 km at the average speeds of 25 km/h and 40 km/h.
First, let's calculate the time taken at an average speed of 25 km/h:
Time = Distance / Speed
Time = 3.50 km / 25 km/h
Time = 0.14 hours
Next, let's calculate the time taken at an average speed of 40 km/h:
Time = Distance / Speed
Time = 3.50 km / 40 km/h
Time = 0.0875 hours
To find the time gained, we subtract the time taken at a speed of 40 km/h from the time taken at a speed of 25 km/h:
Time Gained = Time at 25 km/h - Time at 40 km/h
Time Gained = 0.14 hours - 0.0875 hours
Time Gained = 0.0525 hours
Therefore, the motorist will gain approximately 0.0525 hours, or 3.15 minutes, in his journey.
To find the time saved on the journey when the average speed increases, we need to calculate the time it takes to travel the distance at both speeds, and then compare the difference.
1. Calculate the time taken at the initial average speed of 25 km/h:
- Distance: 3.50 km
- Average speed: 25 km/h
- Time = Distance / Speed
- Time = 3.50 km / 25 km/h
- Time = 0.14 hours
2. Calculate the time taken at the increased average speed of 40 km/h:
- Distance: 3.50 km
- Average speed: 40 km/h
- Time = Distance / Speed
- Time = 3.50 km / 40 km/h
- Time = 0.0875 hours
3. Calculate the time saved:
- Time saved = Initial time - New time
- Time saved = 0.14 hours - 0.0875 hours
- Time saved = 0.0525 hours
Therefore, the motorist will save approximately 0.0525 hours (or 3.15 minutes) on their journey when the average speed increases from 25 km/h to 40 km/h.