Testers are cool at prime numbers

A software tester, a software developer, and a project manager are told: 

“All odd numbers are prime”

The Developer says:

“Let's see, 3 is prime, 5 is prime, 7 is prime - looks like it‟s true”

The Project Manager says:

“Let's see, 3 is prime, 5 is prime, 7 is prime, 9 is prime, 11 is prime –looks like it‟s true.”

The Tester says:

“That's silly, nine is a non-prime odd number - looks like it's bullshit”

I recently heard this very sad anecdote while attending a lecture about Software Testing. 

Everybody (except maybe a Test Manager) knows the developer would look up prime numbers on google before even trying to answer.

Anyway - here's a good resource about odd prime numbers humour.