[Question] Getting cell value and use it in table formula

[jman]

Hello there,

Let's look at the following table:

----------s---------s----------
| EUR |    USD | Exchange rate |
|-----+--------+---------------|
|  10 |   8.97 |         0.897 |
|  15 | 13.455 |               |
#+TBLFM: $2='(* (string-to-number $1) (string-to-number (org-table-get 2 3)))
----------e---------e----------

I've tried a number of things but this is the only incantation is able to retrieve the value from 
the cell "@2$3" and use it into the table formula.

Is there a cleaner way to retrieve a cell value and use it into a table formula that is a lisp 
expression?

Any suggestion? Thanks.

Best,