Can you please explain in more detail?

This a classic combinatorics problem, in which you count the 4 dishes from 12 (the order does not matter) and apply the classic formula.

\(\frac{12*11*10*9*8*7*6*5*4*3*2*1}{(8*7*6*5*4*3*2*1)*(4*3*2*1)} =\)

Simplify

\(3*11*5*3 = 495\)

C is the answer

Not OG Big book Q

Sir how do we sort out which problem is based in permutation which in combination?

A combination is an unordered collection of k objects taken from a set of n distinct objects. The number of ways how we can choose k objects out of n distinct objects is denoted as:

I pick 2 persons among 20...any kind


A permutation is an ordered collection of k objects taken from a set of n distinct objects. The number of ways how we can choose k objects out of n distinct objects is denoted as:


two persons among 20 but first the tallest and then the shortest....


https://gre.myprepclub.com/forum/gre-quant ... 18819.html

Esteban’s restaurant offers a lunch special. A customer can order a platter consisting of four different small dishes from a selection of twelve choices. How many different platters can a customer create?

From a choice of 12 different dishes, he can choose four.

Since the order of dishes does not matter, it is a combination problem.

So, the number of platters that customer can create is \(12C4 \)

\(12C4 = 12!/(12-4)! * 4! = 12!/8! * 4! = 12 * 11 * 10 * 9/4! = 495 \)

The Answer is C.