An airplane travels 2800 km at a speed of 700 km/h, decreases its speed to 500 km/h for the next 1500 km and travels the last 1000 km at a speed of 400 km/hr. Find the average speed of the plane for the trip.
speed=distance/time
Add the total distances up: 2800+1500+1000=5300 km
Solve for time for all parts (remember units)
t=distance/speed
Part A: 2800/700=4 hours
Part B: 1500/500=3 hours
Part C: 1000/400=2.5 hours
Then add all time parts up
4+3+2.5=9.5 hours
Then finally solve for speed total
speed=distance/time
speed=5300 km/9.5 hours
Speed=557.89 km/h
558km/h
How you get yhe answer
Well, let's calculate the total time it takes for the trip first.
For the first part of the trip, the plane travels 2800 km at a speed of 700 km/h, so it takes 2800/700 = 4 hours.
For the second part of the trip, the plane travels 1500 km at a speed of 500 km/h, so it takes 1500/500 = 3 hours.
And for the last part of the trip, the plane travels 1000 km at a speed of 400 km/h, so it takes 1000/400 = 2.5 hours.
So, the total time for the trip is 4 + 3 + 2.5 = 9.5 hours.
Now, let's calculate the total distance traveled:
2800 km + 1500 km + 1000 km = 5300 km.
Finally, let's calculate the average speed:
Average speed = total distance / total time = 5300 km / 9.5 hours ≈ 557.89 km/hr.
Therefore, the average speed of the plane for the trip is approximately 557.89 km/hr.
To find the average speed of the plane for the entire trip, we need to calculate the total distance traveled and the total time taken.
First, let's find the time taken for each segment of the trip:
1. For the first segment, the plane travels 2800 km at a speed of 700 km/h. We can find the time taken using the formula: time = distance / speed.
Therefore, time taken = 2800 km / 700 km/h = 4 hours.
2. For the second segment, the plane travels 1500 km at a speed of 500 km/h.
Similarly, time taken = 1500 km / 500 km/h = 3 hours.
3. For the third segment, the plane travels 1000 km at a speed of 400 km/h.
Again, time taken = 1000 km / 400 km/h = 2.5 hours.
Now, let's find the total distance traveled:
Total distance = 2800 km + 1500 km + 1000 km = 5300 km.
Next, let's find the total time taken for the entire trip:
Total time = 4 hours + 3 hours + 2.5 hours = 9.5 hours.
Finally, we can find the average speed using the formula: average speed = total distance / total time.
Average speed = 5300 km / 9.5 hours = 557.89 km/h (rounded to two decimal places).
Therefore, the average speed of the plane for the entire trip is approximately 557.89 km/h.