SOLUTION: A train travels 110 km in the same time that a plane covers 385 km. If the speed of the plane is 20 km less than 4 times the speed of the train, find both speeds.
I know this is
Algebra ->
Customizable Word Problem Solvers
-> Travel
-> SOLUTION: A train travels 110 km in the same time that a plane covers 385 km. If the speed of the plane is 20 km less than 4 times the speed of the train, find both speeds.
I know this is
Log On
Question 760992: A train travels 110 km in the same time that a plane covers 385 km. If the speed of the plane is 20 km less than 4 times the speed of the train, find both speeds.
I know this is a distance times time gets rate formula problem where the blank has to be filled in be elimination or substitution. All I can figure out is the abbrevations that I want to use for train (t) and plane (p) and the numbers that go with them. t110 and p385. that's all I've come with. Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! A train travels 110 km in the same time that a plane covers 385 km. If the speed of the plane is 20 km less than 4 times the speed of the train, find both speeds.
--------------------------
train DATA:
distance = 110 km ; time = x hrs ; ; rate = 110/x hrs
----------
plane DATA:
distance = 385 km ; time = x hrs ; rate = 385/x hrs
----------------------
Equation:
plane rate = 4*train rate - 20
---
(385/x) = 4(110/x) - 20
-----
385 = 4(110) - 20x
20x = 440-385
20x = 55
x = 11/4 hrs
===========
car rate = 110/(11/4) = 440/11 = 40 km/hr
---
plane rate = 385/(11/4) = 140 km/hr
==========================================
Cheers,
Stan H.
======================