These questions are meant to prepare you for the coding challenge. You should read each question and try to solve them for yourself. Solutions are provided, look at those after making your attempt at the problem. Make sure you understand the solutions.
We've noted a difficulty level for each problem. The easy ones are a little easier than the problems you'll see on the challenge, the medium ones are a good proxy for the difficulty of the challenge, and the hard ones are generally harder than those you'll encounter on the challenge.
Each of these practice problems is an individual Ruby file. Run the file; if any "false" is output, then your program contains an error.
If you would like to review the Introduction to Programming Minibook, a recap of the various topics are available here: Introduction To Programming Summary.
We strongly recommend you use Cloud9 (c9.io) to do the practice problems. See our setup instructions for instructions on how to use Cloud9.