second_num=$2
# upper bound is first_num * 110%
- upper=$(( $first_num + $first_num / 10 ))
+ upper=$(expr $first_num + $first_num / 10 )
# lower bound is first_num * 90%
- lower=$(( $first_num - $first_num / 10 ))
+ lower=$(expr $first_num - $first_num / 10 )
if [ $second_num -gt $upper ] || [ $second_num -lt $lower ]; then
echo "The difference between $first_num and $second_num are greater than 10%."