Question

How many different ways can a teacher select 3 students from a class of 15 students to each perform a different classroom task?

Answer 1

Answer: 455ways

Step-by-step explanation:

This can be done according to rule of combination because it talks about selection.

In order to select r object from a pool of n objects, it is represented as nCr = n!/(n-r)!r!

Therefore to select 3 students from a class of 15students, this will give us 15C3.

15C3 = 15!/(15-3)!3!

= 15!/12!3!

= 15×14×13×12!/12!×6

= 15×14×13/6

= 455ways

This selection can be done in 455ways