Answer :
Final answer:
The journey takes 50 minutes at 80 km/h compared to 40 minutes at 100 km/h.
Explanation:
To find the time taken at 80 km/h:
- Calculate the time taken at 100 km/h: 40 minutes.
- As speed is inversely proportional to time, the ratio of time at 80 km/h to 100 km/h is 100/80.
- Therefore, the same journey at 80 km/h will take 50 minutes.
Final answer:
If Peter travels at 100 km/h, a 40-minute journey is equivalent to traveling 200/3 km. When traveling at 80 km/h, the journey would take 2.5 hours or 2 hours and 30 minutes to complete the same distance.
Explanation:
If Peter travels at 100 km/h, the journey takes 40 minutes. First, we need to determine the distance of the journey. We convert 40 minutes to hours by dividing by 60 (since there are 60 minutes in an hour), which gives us 40/60 = 2/3 hours. The distance (d) can be calculated using the formula d = speed × time. Substituting the speed of 100 km/h and the time of 2/3 hours, we get:
d = 100 km/h × 2/3 h = 200/3 km
Now, let's calculate the time taken for the same journey at a speed of 80 km/h using this distance:
time = distance/speed
So:
time = (200/3) km / 80 km/h = 2.5 hours = 2 hours 30 minutes
Hence, the journey would take Peter 2 hours and 30 minutes if he travels at 80 km/h.
