SOLUTION: Please help me solve this word problem: It takes a freight train 2 hours more to travel 300 miles than it takes an express train to travel 280 miles. the rate of the express train
Algebra.Com
Question 423820: Please help me solve this word problem: It takes a freight train 2 hours more to travel 300 miles than it takes an express train to travel 280 miles. the rate of the express train is 20 miles per hour faster than the rate of the freight train. Find the rates of both trains.
I have been working on this problem for 3 days.
Answer by sudhanshu_kmr(1152) (Show Source): You can put this solution on YOUR website!
speed of freight train = x mph
speed of express train = x+20 mph
time taken by freight train for 300 miles = 300/x hrs
time taken by express train for 280 miles = 280/(x+20) hrs
300/x = 280/(x+20) + 2
=> 300/x - 280/(x+20) = 2
=> [ 300(x+20) -280x]/x(x+20) = 2
=>[ 20x + 6000] = 2(x^2 +20x)
=> 20x + 6000 = 2x^2 + 40x
=> 2x^2 + 20x - 6000 = 0
=> x^2 + 10x - 3000 = 0
=> x^2 + 60x - 50x - 3000 = 0
=> x(x+60) -50(x +60)=0
=>(x-50)(x+60) = 0
now, x=50 mph because, x= -60 not possible.
so, speed of freight train = 50 mph
speed of express train = 70 mph
if any doubt, please contact....
RELATED QUESTIONS
it takes a freight train 3 hours more to travel 200 miles than it takes an express train... (answered by ankor@dixie-net.com)
The speed of a passenger train is 18 mph faster than the speed of a freight train.The... (answered by checkley77)
Please help me solve this word problem: The express train traveled at a speed that was... (answered by jorel1380)
A freight train takes 2 hours longer to travel 300 miles than an express train to travel... (answered by checkley77)
Can you help me solve this problem:
It takes a passenger train 2 hours less time than... (answered by TakeATuition.com)
It takes a freight train 2 hrs longer to travel 300 miles than it takes an express train... (answered by Paul,stanbon)
It takes a freight train 3 hours more to travel 200 miles than it takes an express train... (answered by scott8148)
It takes a freight train 2 hours longer to travel 200 miles than it takes an express... (answered by stanbon)
It takes a freight train 3 hours more to travel 280 miles than it takes an express train... (answered by mananth)