Yes; I too got stuck but I figured it out (on Windows 7 OS). Here it goes, explained:
First off, I made a desktop folder, named Jesse’s Programs Folder. Second, I made my “calc” file into calc.txt format because windows 7 made it difficult to attempt to make the file into a ruby file. But no matter! Here’s what I figured out to do:
My command line looks similar to this (and the steps I took to solve my problem):
Step 1: By default my command line reads this: C:\Users\Jesse Jimenez>
Step 2: I did the following command: C:\Users\Jesse Jimenez> cd desktop
Step 3: C:\Users\Jesse Jimenez\Desktop> cd Jesse’s Programs Folder
Step 4: I then use “dir/ad” to find my file under my directory on ruby: “C:\Users\Jesse Jimenez\Desktop\Jesse’s Programs Folder> dir/ad” to find my file under the command line and I found it based on the approximate time and date I saved the file and the name of the file.
Step 5: I then did this command: “C:\Users\Jesse Jimenez\Desktop\Jesse’s Programs Folder>move calc.txt calc.rb” and the a command prompt stated that my file had changed from a .txt file to a .rb file
Step 6: Finally, I did this: “C:\Users\Jesse Jimenez\Desktop\Jesse’s Programs Folder>ruby calc.rb” At last, I got the calculation of 3!
Hope this all helps!