Suto wrote:

Dear All,

I know this is not a GMAT question but it is very similar. Could someone explain how to answer this question ?

I am with a group of five of my friends. A box contains 8 pieces each of milk chocolate, white chocolate, and dark chocolate. The box is passed around the six of us, with each person taking 4 pieces. Assume that each person chooses at random without replacement from the available pieces. I am the last person to whom the box is passed. Find the chance that I pick 4 dark chocolates.

Thank you very much in advance.

Warm regards,

Olivier

Ok, let me give you some ideas. Perhaps you will be able to figure it out.

It doesn't matter whether I am the last person or the first. Since each person is an equal element, the probability that any one picks 4 dark chocolates is the same. Also the probability of picking 4 dark chocolates in the first pick is same as picking 4 dark chocolates in the last pick.

The logic behind it is a little un-intuitive but I have discussed it in detail in this post. Check it out:

http://www.veritasprep.com/blog/2012/10 ... ure-again/Now we need to find the probability of picking 4 dark chocolates in the first pick.

Find the total number of ways in which you can pick 4 chocolates:

all 4 same type,

3 same type 1 different,

2 same 2 same,

2 same 2 different

_________________

Karishma

Veritas Prep | GMAT Instructor

My Blog

Get started with Veritas Prep GMAT On Demand for $199

Veritas Prep Reviews