# 100! - 99!

#### srfriggen

question: what is 100! - 99!

I've broken it down to a problem like this: Let x=99! Then 100! = 100*99! = 100x. 100x - x=99x = 99*99!.

I can't figure out a way to simplify the problem any more than that.

Thank you in advance for any help.

#### HallsofIvy

Homework Helper
There is the obvious: 100!- 99!= 99!(100- 1)= 99!(99).

#### phinds

Gold Member
you've got the right answer and I don't see how it COULD be simplified any further except by actually computing 99! which just seems like a waste of time.

Homework Helper

Mentor

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#### arildno

Homework Helper
Gold Member
Dearly Missed
As is seen, "!" does not satisfy the distributive law for operations.

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