Porcentaje de uso cpu y ram

#!/bin/bash
totalram=$(free | grep Mem | awk '{print $2}')
enusoram=$(free | grep Mem | awk '{print $3}')
carga=$(uptime | awk 'NF{print $(NF-1)}' | sed 's/\.//g' | sed 's/\,//g' )
cpus=$(lscpu | grep CPU\(s\)| head -n1 | awk '{print $2}')
let ram=$enusoram*100/$totalram
let cpu=$(($carga))/$(($cpus))
echo $(hostname) cpu=$cpu %  ram=$ram %