How many different ways can the front row seats be filled with 20 students if the classroom has 4 rows of seats? 1,860,480 116,280 4,845?

Question

asked Jan 24, 2019 17.9k views

2 Answers

Roshil K · Answer 1 · 2019-01-27T21:56:27+0000

we know that

The formula for combinations is

C=n!/((n-r)!*r!)

where

n is the total number of objects you choose from

r is the number that you choose to arrange

in this problem

$n=20\\ r=4$

$C=20!/[(20-4)!*4!]\\ C=20!/[(16)!*4!]\\ C=4,845$

therefore

the answer is