SOLUTION: Two escaped convicts are headed east on the railroad tracks. They come to a mile-long tunnel; they have little choice but to enter. They are 0.4 mile into the tunnel when they hear

Question 736991: Two escaped convicts are headed east on the railroad tracks. They come to a mile-long tunnel; they have little choice but to enter. They are 0.4 mile into the tunnel when they hear an eastbound train closing in on them from behind. Oh no!
Snap decisions are required. The younger, faster convict decides to run the 0.4 mile back out of the tunnel (even though the train is coming at him!). The older and slower convict decides to run the remaining 0.6 mile to the far end of the tunnel. (He will run away from the train because it gives him more time to escape.)
The fast convict runs at 11 miles per hour; the slower convict runs at 7 miles per hour. The train travels at a steady rate. Each man manages to exit the tunnel at the last possible second. Close calls!
Question: what was the speed of the train?
Answer by ankor@dixie-net.com(22740) (Show Source): You can put this solution on YOUR website!
Two escaped convicts are headed east on the railroad tracks.
They come to a mile-long tunnel; they have little choice but to enter.
They are 0.4 mile into the tunnel when they hear an eastbound train closing in on them from behind. Oh no!
Snap decisions are required.
The younger, faster convict decides to run the 0.4 mile back out of the tunnel (even though the train is coming at him!).
The older and slower convict decides to run the remaining 0.6 mile to the far end of the tunnel.
(He will run away from the train because it gives him more time to escape.)
The fast convict runs at 11 miles per hour; the slower convict runs at 7 miles per hour.
The train travels at a steady rate.
Each man manages to exit the tunnel at the last possible second. Close calls!
Question: what was the speed of the train?
:
Find the time required by the faster guy to get to the near end of the tunnel
.4/11
At this time the train enters the tunnel
The slower guy has traveled 7 * .4/11 = .25454 mi so he is:
.6 - .25454 = .3454 mi to the end of the tunnel
He has to travel .3454 mi while the train travels 1 mile
let t = speed of the train
=
Cross multiply
.3454t = 7*1
t =
t = 20.3 mph is the speed of the train
RELATED QUESTIONS
Train tracks are made of metal. Consequently, they expand when it�s warm and shrink when... (answered by Theo)

Two trains are traveling toward each other on parallel tracks They start at the same... (answered by solver91311,Edwin McCravy)

The world is three dimensional, but drawings are done in a two dimensional surface, we... (answered by ikleyn)

Amtrail provides efficient nonstop transportation between Los Angeles and San Diego.... (answered by lwsshak3)

Suppose the New York City and St. Louis railroad stations are 100 miles apart via the... (answered by Alan3354)

two locomotives approach each other on parallel tracks. Each has a speed of 95 km/h with... (answered by oberobic,fcabanski)

A railway company is building a new railroad. Surveyors wish to measure the height of a... (answered by mananth)

A railroad has a tunnel 5 miles long. A train which is 440 yards long enters the tunnel... (answered by checkley77)

a passenger train leaves chicago at the same time a freight train leaves new york. the... (answered by mananth)