[O] is this spreadsheet correct?

[Samuel Wales]

Also, I entered the formula as =rp=, but it got put in as
$5.

| ! | what    |  pw |   ph |    rp | ew | eh |  re |          f |
|   | current | 720 | 1152 | 0.625 | 71 | 23 | 3.1 | 0.51612903 |
#+TBLFM: $5=$pw/$ph

C-c '

Debugger entered--Lisp error: (wrong-type-argument number-or-marker-p nil)
  org-edit-src-code()
  org-edit-special()
  call-interactively(org-edit-special nil nil)

-- 
The Kafka Pandemic: http://thekafkapandemic.blogspot.com

The disease DOES progress.  MANY people have died from it.  ANYBODY
can get it.  There is no hope without action.