numaverage: 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/numaverage - from package: num-utils

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

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