Sometimes Ruby's faster, sometimes Python is.

However all those benchmarks are probably useless. They are not testing how the language is used or should be. The trick with all the scripting languages is to make the CPU spend most of its time in the C code inside the standard library or the implementation of the native constructs of the language with as little overhead as possible.

Example: you don't want to do numerical computation using plain Python, you want to use Numpy.

You also want to learn very well all the ways Ruby's standard library can group operations in a single method call saving time compared to naive multi method chains.