SOLUTION: flight 725 left new york at 10:28am flying north. flight 245 left same airport at 11:18am flying south at 125kmh less than 3 times the speed of flight 725. at 1:06pm they are 1030

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: flight 725 left new york at 10:28am flying north. flight 245 left same airport at 11:18am flying south at 125kmh less than 3 times the speed of flight 725. at 1:06pm they are 1030       Log On


   



Question 187617: flight 725 left new york at 10:28am flying north. flight 245 left same airport at 11:18am flying south at 125kmh less than 3 times the speed of flight 725. at 1:06pm they are 1030 km apart. what is average rate of speed for flight 245?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
flight 725 left new york at 10:28am flying north. flight 245 left same airport
at 11:18am flying south at 125kmh less than 3 times the speed of flight 725.
at 1:06pm they are 1030 km apart. what is average rate of speed for flight 245?
:
Let s = speed of flt 725
;
then is says,"flt 245 flies 125kmh less than 3 times the speed of flight 725."
therefore:
(3s-125) = speed of flt 245
:
Travel times of both aircraft (Change 1:06 to 13:06):
;
Flt 725: 13:06 - 10:28 = 2 hr 38 min ~ 2.633 hrs
Flt 245: 13:06 - 11:18 = 1 hr 48 min = 1.8 hrs
:
Write a dist equation: dist = time * speed
:
Flt 725 dist + Flt 245 dist = 1030 km
2.633s + 1.8(3s-125) = 1030
2.633s + 5.4s - 225 = 1030
2.633s + 5.4s = 1030 + 225
8.033s = 1255
s = 1255%2F8.033
s = 156.23 km/hr is the speed of flt 725
:
but they want the speed of 245
3(156.23) - 125 = 343.69 km/hr is the speed of flt 245
:
:
Check solution by finding the distance of each at 1:06
2.633 * 156.23 =411.35
1.8 * 343.69 = 618.64
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total distance = 1029.99 ~ 1030; confirms our solutions