I'm new to Linux and I’m trying to write a simple script to reference lines in a text file and perform math. I have the basics of what I from doing some research online but I cant find how to reference text within a text file.
var2= "needs to referance line 4 of file calc2"
var3= "needs to referance line 5 of fil calc3"
var4=$[$var2 / $var3]
echo calculation is $var4