Write a shell script to perform mathematical operation using select case

 Write a shell script to perform mathematical operation using select case

echo "enter the two number"

read a b

echo "1:addition/n2:subtraction/n3:multipication/n4:divison"

read c

case "$c" in

1)z=`expr $a + $b`;;

2)z=`expr $a - $b`;;

3)z=`expr $a /* $b`;;

4)z=`expr $a / $b`;;

esac