If I let my son up to his own devices, he sometimes builds weird things like this.

Act 2
I'm going with the question, "If Emmett wants to make the largest pyramid he can, how many cups do I have to buy? How much will that cost me?"
So we need some measurements.... I don't have any of them yet, but I'll work on it.

cup height - 4 1/2 inches
height of my ceiling - 93 1/2 inches
top width (open side) - 3 7/8 inches
bottom width - 2 7/16 inches
cost for a bag of cups -
number of cups in a bag -

Act 3
I will make act 3. And it will really annoy my wife. Yes, I will make act 3.

Sequel
Kelly Berg (@KmBergie) suggested a square pyramid. Then I thought, why not triangular? And what will limit the pyramids' sizes...ceiling or floor space?

So I went to Staples to buy some cups. They were on sale...50 cups for 50 cents. Unfortunately they weren't the same size as the other cups, but I was able to buy a lot of them. So I bought every package they had, went home, and made the largest triangular pyramid I could with them.

So my question is: if I made the tower as tall as I could, how many leftover cups were there?

Sequel 2:
This is becoming a page where I just post random things we've done with plastic cups. Here are some pictures of our last design:

If I let my son up to his own devices, he sometimes builds weird things like this.

Act 2

I'm going with the question, "If Emmett wants to make the largest pyramid he can, how many cups do I have to buy? How much will that cost me?"

So we need some measurements.... I don't have any of them yet, but I'll work on it.

cup height - 4 1/2 inches

height of my ceiling - 93 1/2 inches

top width (open side) - 3 7/8 inches

bottom width - 2 7/16 inches

cost for a bag of cups -

number of cups in a bag -

Act 3

I will make act 3. And it will really annoy my wife. Yes, I will make act 3.

Sequel

Kelly Berg (@KmBergie) suggested a square pyramid. Then I thought, why not triangular? And what will limit the pyramids' sizes...ceiling or floor space?

So I went to Staples to buy some cups. They were on sale...50 cups for 50 cents. Unfortunately they weren't the same size as the other cups, but I was able to buy a lot of them. So I bought every package they had, went home, and made the largest triangular pyramid I could with them.

So my question is: if I made the tower as tall as I could, how many leftover cups were there?

Sequel 2:

This is becoming a page where I just post random things we've done with plastic cups. Here are some pictures of our last design:

Exploding Cups from Nathan Kraft on Vimeo.

Act 3

Although the answer to the triangular pyramid should be obvious, Fawn Nguyen requested that I post the answer here...560 cups.