Question

The number of ways 8 cars can be lined up at a toll booth would be computed from

a. 8 to the 8th power
b. (8)*(8)
c. 8!
d. 8!/7!1!

Answer 1

Answer: c. 8!

Explanation:

We know , that if we line up n things , then the total number of ways to arrange n things in a line is given by :-

`n!` ( in words :- n factorial)

Therefore , the number of ways 8 cars can be lined up at a toll booth would be 8! .

Hence, the correct answer is c. 8! .

Alternatively , we also use multiplicative principle,

If we line up 8 cars , first we fix one car , then the number of choices for the next place will be 7 , after that we fix second car ,then the number of choices for the next place will be 6 , and so on..

So , the total number of ways to line up 8 cars = 8 x 7 x 6 x 5 x 4 x 3 x 2 x1 = 8!

Hence, the correct answer is c. 8! .