Shell Programming - Arithmetic operations

# Shell Programming
# Arithmetic Operations

echo "Menu"

echo "1 - Addition"

echo "2 - Subtraction"

echo "3 - Multiplication"

echo "4 - Division"

echo -n "Enter your choice : "

read n

echo -n "Enter the numbers : "

read a b

case $n in

1) echo "Sum of $a and $b is `expr $a + $b`";;

2) echo "Difference of $a and $b is `expr $a - $b`";;

3) echo "Product of $a and $b is `expr $a \* $b`";;

4) echo "Division of $a by $b is `expr $a / $b`";;

*) echo "Invalid choice";;

esac