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[Corey Hokanson <716183@xxxxxxxxxxxxxxxxxx>]

Public bug reported:

Binary package hint: gbrainy

Problem Text

A train leaves the station traveling at 35 mph. 4 hours later a second
train leaves the station traveling in the same direction at 55 mph. How
many hours does it take the second train to overtake the first train?


Correct answer:

The first train has traveled 4 hours at 35 mph, so it has a 140 mile
lead on the second train. The second train is going 55 mph, 20 mph
faster than the first train. So when the second train sets out from the
station, it will take 7 hours to travel the extra 140 miles and catch
up.

7 hours.


Program's answer

"Incorrect answer. The correct answer is 11. You can calculate the
answer multiplying the second train speed by the time and dividing it by
the difference of speeds."

Problem with the program's answer:

The program is multiplying the second train's speed by the time of the
headstart, which means the program is incorrectly giving the second
train the headstart, even though the first train was the one with the
headstart.

ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: gbrainy 1.51-0ubuntu1
ProcVersionSignature: Ubuntu 2.6.35-25.44-generic 2.6.35.10
Uname: Linux 2.6.35-25-generic i686
NonfreeKernelModules: fglrx wl
Architecture: i386
Date: Wed Feb  9 18:40:11 2011
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Release i386 (20101007)
PackageArchitecture: all
ProcEnviron:
 LANG=en_US.utf8
 SHELL=/bin/bash
SourcePackage: gbrainy

** Affects: gbrainy (Ubuntu)
     Importance: Undecided
         Status: New


** Tags: apport-bug i386 maverick

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https://bugs.launchpad.net/bugs/716183

Title:
  Math is wrong on train problem