Question

Suppose we want to choose 2 letters, without replacement, from the 5 letters A,B,C,D, and E

Answer 1

Step-by-step explanation

We are asked to choose 2 letters from 5 without replacement

To do so,

When selecting more than one item without replacement and order is important, it is called a Permutation. When the order is not important, it is called a Combination.

we are to consider two scenarios

Part A

The first one is when the order matters

When the order is relevant, we will have permutation

`^5P_2=(5*4*3!)/((5-2)!)=5*4=20\text{ ways}`

Part B

When the order is not relevant, we will have combination

`^5C_2=(5*4*3!)/(2!*(5-2)!)=(20)/(2)=10\text{ WAYS}`

c