231k views
14 votes
There are 18 students on the debate club. How many ways can the club send 4 students to the next debate?.

User Whatsit
by
6.9k points

1 Answer

8 votes

Let's consider first what equation we must use:

⇒ use Combination Formula ⇒
._(n) C_(r)=(n!)/(r!(n-r)!)

⇒ where 'n' is the total number of items and 'r'

is the number of items to choose

Let's look at the problem:

  • total number of students: 18
  • number of students needed for debate: 4

Let's plug it in:


(18!)/(4!*(18-4)!) =(18!)/(4!*14!) =(18*17*16*15)/(4*3*2*1) =18*17*2*5=3060

Thus there are 3060 ways

Answer: 3060 ways

Hope that helps!

User Ianpojman
by
6.5k points