Write a shell script to generate marksheet of a student. Take 3 subjects, calculate and display total marks, percentage and Class obtained by the student

 echo "Enter marks(out of 30) of "

read -p "Subject 1: " s1

read -p "Subject 2: " s2

read -p "Subject 3: " s3

sum=`expr $s1 + $s2 + $s3`

echo "Sum of marks of 3 subjects is : "$sum

per=`expr $sum \* 10 / 9`

echo "Percentage: "$per

if [ $per -ge 60 ]

then

        echo "you got Distinction"

elif [ $per -ge 50 ]

then

        echo "you got First class"

elif [ $per -ge 40 ]

then

        echo "You got second class"

else

        echo "sorry you failed! better luck next time"

fi