These downloads are for outdated versions, which are no longer maintained.
For current and newer versions, please go to the web site for Racket.
Package:   Download PLT Scheme
Version:   200
Platform:   Macintosh OS X (PPC)
Type:   Disk Image
File:   plt-200-bin-ppc-osx-mac.dmg
Size:   4.1Mb

Download links:     (Choose the nearest site)

Installation instructions
Download the file, and double-click it in the Finder to mount the disk image. Finder will start the Disk Copy utility to mount the image.
Once this is done, double-click the mounted image on the desktop to open its window Finder window (if it was not opened automatically). In this folder you will find a package icon (an mpkg file) — double click it to install the software. Finder will start the Installer utility to perform the installation.
The installation will place the Download PLT Scheme files in /Applications/PLT and support frameworks in /Library/Frameworks.
(Software License)