Krause Foundation



Fore the love of math: An equation posed by a really big hole

If a golf ball is 1.68 inches in diameter and a hole is 65,000 cubic yards, how many golf balls would it take to fill the hole?

Sound like a fifth grade word problem? Maybe. After all, your math teacher told you you’d need to use those skills someday.

For Ryan Companies, that day was earlier last month when Kum & Go’s marketing team asked them to quantify just how big the hole was that had been dug as the foundation for the company’s new corporate headquarters in downtown Des Moines.

Excavation of the Krause Gateway Center site was complete in mid-April. The resulting hole, which is 3-stories at its deepest point, will be filled in with two stories of below-grade parking for 225 vehicles. In the end, 65,000 cubic yards of material were removed.

That’s a big hole. So big that Kum & Go wanted another way to quantify the size. So, Ryan Companies, the contractor for the project, which is designed by OPN Architects and Renzo Piano, did some math. They calculated that the hole is the equivalent to 20 Olympic swimming pools with a capacity to hold 13,170,725 gallons of water. It would take 8,400,761 hard hats and 95,039,055 soda cans to fill it.

And what about the golf balls? You would need 900,561,576. That’s a lot of duffs.

We decided to take it one step further and convert this into a unit that designers will be more familiar with: beer. You could pour the equivalent of 105,365,806 US pints or 87,735,386 imperial pints into the hole. Not that you’d want to waste that much beer.