Question

Just need some help with the second answer thanks :)

Answer 1

4,151,347,200

Explanation:

To find how many ways the train can be made up we use the permutation formula and the values given.

n = 16

k = 9

`_(n)P_(k)=(n!)/((n-k)!)`

`_(16)P_(9)=(16!)/((16-9)!)`

`_(16)P_(9)=(16!)/(7!)`

`_(16)P_(9)=4,151,347,200`

So there will be 4,151,347,200 different ways that the train can be made.