How do I divide in the Linux console?

I have to variables and I want to find the value of one divided by the other. What commands should I use to do this?

In the bash shell, surround arithmetic expressions with $(( ... ))

$ echo $(( 7 / 3 ))
2

Although I think you are limited to integers.

echo 5/2 | bc -l

2.50000000000000000000

this '-l' option in 'bc' allows floating results

Better way is to use "bc", an arbitrary precision calculator.

variable=$(echo "OPTIONS; OPERATIONS" | bc)

ex:

my_var=$(echo "scale=5; $temp_var/100 + $temp_var2" | bc)

where "scale=5" is accuracy.

man bc 

comes with several usage examples.

You can use awk which is a utility/language designed for data extraction

e.g. for 1.2/3.4

>echo 1.2 3.4 | awk '{ print $2/$1 }'
0.352941