Tatiana is a counselor at summer camp. She wants to take 20 campers on a hike and wants to choose a pair of students to lead the way. In how many ways can Tatiana choose this pair of children?

Respuesta :

Answer:

There are 190 ways to choose this pair of children

Step-by-step explanation:

Total number of students at summer camp = 20

Tatiana wants to choose a pair of students to lead the way

Number of students in a pair = 2

We are supposed to find In how many ways can Tatiana choose this pair of children

So, We will use combination

Formula :[tex]^nC_r=\frac{n!}{r!(n-r)!}[/tex]

n = 20

r= 2

So,[tex]^nC_r=\frac{n!}{r!(n-r)!}=\frac{20!}{2!(20-2)!}=190[/tex]

Hence There are 190 ways to choose this pair of children