Question 883601
A train is traveling at a constant rate.
 If it passes through a 360 meter long tunnel, it takes 16 seconds.
 If the train passes over a 1.2 kilometre bridge, it takes 40 seconds.
 How long is the train?
:
Change 1.2 km to 1200 meters
:
Let s = the speed of the train
Let L = the length of the train
:
Write an equation for each scenario
:
Find the speed
L + 1200 = 40s
L + 360 = 16s
-----------------Subtraction eliminates L, find s
840 = 24s
s = 840/24
s = 35 km/hr is the speed of the train
:
Find L
L + 360 = 16(35)
L + 360 = 560
L = 560 - 360
L = 200 meters is the length of the train
:
;
Confirm this by finding the length using the other equation
L + 1200 = 40(35)
L = 1400 - 1200
L = 200 meters