Life is A Test 2: Test Harder (Quite A Bit Harder)

by Brony_of_Brody

Saving Utterly Flutterly Butterly

It takes a lot of candy munching, but eventually you and Rainbow Dash manage to eat her way to safety and freedom. She is then given a crash course on what to expect when the time comes to rescue Fluttershy, which causes no end of horrifying descriptions and images from each member of the team as you journey straight to the top of the mountain. Which is even more impressive, given it's hard to tell through the oxygen masks what you're trying to say.

However, as soon as you actually find Fluttershy, she is in fact seemingly completely unharmed, with absolutely no obstacle or nefarious trap to be found. upon being questioned, she reveals a mysterious spooky voice told her that her friends would come to collect her and was told to wait where she was.

That just raises the question of why she didn't just go back down the mountain, and she answers that she 'didn't want to disappoint whoever that was'. All six of her rescuers including you manage a perfect 10/10 in synchronised face-hoofing.

However, Fluttershy does at least manage to shed a bit more light on what the deal is with the mountain and the forces at work. The spooky voice's owner is apparently something trying to study the logic of this world, and so mare-napped the ponies who were closest to probably the most accomplished puzzle-solver in Equestria - you, in order to observe such brilliant logic in action. Oh cosmos, how they flatter you. With that said, Fluttershy also mentions that it wasn't above observing how that logic could also be taught to others, and so Rainbow Dash has been instructed to try solving the following puzzle that Fluttershy was rather graciously given written on a piece of paper:

How many zeroes are there at the end of 100! ?

At first, Rainbow is quick to just point out that they should really just grab Fluttershy and leave, but is quickly told that all who turn back without solving a puzzle will be quickly given a rather unpleasant bath in flesh-melting acid from the geysers below the mountain. Along with all their unfortunate allies. Please don't make them do that.

Having been coerced by whoever the heck it is, Rainbow settles down to think, after being told that they can go on ahead if they manage to just do this teeny-tiny favour for them. What a drag. Still, can Rainbow solve it and allow the group to meet the guy in charge?

Author's Note:

1. A value of 100!
2. You may not use a calculator.

PUZZLE: How many zeroes are there at the end of 100! (100 x 99 x 98 x 97...x 3 x 2 x 1)?

Comments

[Duckgame4life]

Easy
24
There is 10 numbers that end in 0: 10,20,30 etc
10 from all the ones ending in 5:5,15,25 etc
And 1 extra each for 25,50,75&100

Also the question initially ask how many zeroes in 100!, of with there is another 6 in the middle of it for a total of 30

[ScopingLandscape]

Answer: 24
Because you have 11 from 10, 20, 30,...
Then you have 10 more from even numbers (2, 4, 6,...) excluding the above, times numbers that end in 5 (5, 15, 25,...).
Adding 3 more because 25, 50 and 75 can make 2.
Add all together, that makes 24.
I wanna see how this goes.

[Brony_of_Brody]

9425404
Oh good catch. Fixed