Question 466040: A plane flying at 300 miles per hour has a 3 hr head start on a chase plane which has a speed of 800 mph. How far from the airport will the chase plane overtake the first plane?
Found 2 solutions by ewatrrr, katealdridge:
Answer by ewatrrr(24785)   (Show Source):
You can put this solution on YOUR website!
Hi,
Note: D = r*t
Let x and (x + 3) represent the time for 800mph plane and the 300mph place respectively
800x = 300(x+3)
500x = 900
x = 9/5 hrs, time it will take the chase plane to overtake the first plane
D = 800*9/5 = 1440 mi from the airport
Answer by katealdridge(100)  (Show Source):
You can put this solution on YOUR website! First let's organize the information...
Plane A: Leaves at t-0, Speed=300mph, D=unknown
Plane B: Leaves at t-3, Speed=800mph, D=unknown
However, since the question asks when the one plane overtakes the other, they are essentially asking for the distances to be equal.
Here's a good way to set up these kinds of problems:
D=R*T (distance=rate*time)
Plane A: D=300*t
Plane B: D=800(t-3)
Now set the equation equal to each other and solve for t.
300t=800(t-3)
300t=800t-2400
-500t=-2400
t=4.8
This means that when the two planes have traveled the same distance, it has been 4.8 hours. However, keep in mind, that this is 4.8 hours since the first plane left. Now substitute this value for t in either equation.
D=300(4.8)=1440
1440 miles
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