Question

In how many ways could you choose two different letters from the letters c, o, u, n, t?

Answer 1

$\displaystyle \binom{5}{2}=\dfrac{5!}{2!3!}=\dfrac{4\cdot5}{2}=10\implies \text{D}$

Answer 2

Answer:

Option D is correct.

Step-by-step explanation:

Total number of letters = c , o , u , n , t

We have to find: Numbers of ways in which two letters can be choose.

Combination is used to find numbers of ways.

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

Number of ways = $^{5}\textrm{C}_{2}=\frac{5!}{2!\times(5-2)!}$

$=\frac{5!}{2!\times3!}=\frac{5\times4}{2}=5\times2=10$

Therefore, Option D is correct.