count=`cat /filecount.txt | tail -1 |head -1| awk '{print $1}'`  ###file is having value 264  ####

echo "actual count = $count"

exact_count=`expr $value \* 24`

echo "exact_count= $exact_count"

diff=`expr "$exact_count" - "$count"`

a= exact_count - count

echo " value is &a"
echo "$diff"

actual count = 264
exact_count= 264
expr: An integer value was expected.

temp[55]: exact_count:  not found.
 value is &a

temp[55]: exact_count:  not found.
 value is &a