New section : THINK IT THROUGH! (updated)

Hello, today we open up a small section called: THINK IT THROUGH! You will find interesting problems to ponder and do, here goes :-

THINK IT THROUGH!

Five balls are randomly chosen, without replacement, from an urn that contains 5 red, 6 white and 7 blue balls. Find the probability that at least one ball of each colour is chosen.

Feel free to write in your answers via our comments section below.

We would love to hear from you, cheers.

p/s : Solution coming soon. Try first.

UPDATE:

Solution :
[gview file=”think-it-through-solution.pdf” height=”600px” width=”100%”]