Question

Count the possible combinations of r letters chosen from the given list P.Q,R,S,T,U; r = 2

Answer 1

Answer:

There are 30 possible combinations of picking two letters.

Step-by-step explanation:

The combinations are defined as

$C^{r}_{n}=\frac{n!}{(n-r)!}$

Where $n$ is the total number of elements and $r$ is the number of letter we are gonna picke, which is two. Using this information, we have

$C^{2}_{6}=\frac{6!}{(6-2)!}=\frac{6!}{4!}=\frac{6 \times 5 \times 4!}{4!}=30$

Therefore, there are 30 possible combinations of picking two letters.