$ echo $(( $RANDOM % 10 ))
$(((RANDOM % $((upperBound - lowerBound))) + lowerBound))
#If you have coreutils installed and want a number inbewtween a value
shuf -i MIN-MAX -n 1
#or you can use bash
$RANDOM
$ echo $((1 + $RANDOM % 10))
3
echo $RANDOM
echo $(( $RANDOM % 50 + 1 ))