I want to write a code that will look for a particular directory which is full or more than 95% used, and will search older file and delete it. My code looks like this:

df -k|while read f1 f2 f3 f4 f5 f6
do

if expr '$f5' -ge '95%' || continue
 then
 echo $f5
 else
 echo "there is no critical situation!"
fi
done

find . -name "*" -size +100k |sort -nr |tail -1\
#find /cbmdata/00/gdd -name "LOGS*" |sort -nr |tail -1\
while read line
 do rm -f $line
done

df -k | tr -d '%' | \
while read a b c d 
do
# do stuff 
done

I tried your code and worked, thanks.
last updated code :

ref=95
rep=0

df -k | tr -d '%' | \
while read a b c d e other
do

if (( $e >= $ref )) || continue
then
 rep=$e
 echo $rep

fi
done