plt-r5rs: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/plt-r5rs - from package: racket

You may install the required package with command apt-get install {package}

Error in other languages:
plt-r5rs: bevel nie gevind nie
plt-r5rs: comandă negăsită
plt-r5rs: comando não encontrado
plt-r5rs: commande introuvable
plt-r5rs: command not found
plt-r5rs: käsku ei ole
plt-r5rs: không tìm thấy lệnh
plt-r5rs: komanda nerasta
plt-r5rs: Kommando nicht gefunden.
plt-r5rs: kommandot finns inte
plt-r5rs: komut yok
plt-r5rs: nie znaleziono polecenia
plt-r5rs: níor aimsíodh an t-ordú
plt-r5rs: no se encontró la orden
plt-r5rs: no s'ha trobat l'ordre
plt-r5rs: opdracht niet gevonden
plt-r5rs: parancs nem található
plt-r5rs: perintah tidak ditemukan
plt-r5rs: príkaz nenájdený
plt-r5rs: příkaz nenalezen
plt-r5rs: команда не найдена
plt-r5rs: командата не е открита
plt-r5rs: 命令找不到
plt-r5rs: コマンドが見つかりません