How big is a trillion?

How big is a trillion?
How much is really much? How much is a billion $ or a trillion $? What would you answer? When we are honest we can hardly estimate the real dimensions of the numbers which are often presented in the daily news. We just get used to it. And, of course with the exception of Dagobert Duck, it is not easy to imagine the heights of the gigantic mountain of one trillion € in €100 bills.

In order to give the students a feeling for the incredible sum, I thought up the following exercise in 2015 in a workshop for financial education:
Here, I wrote the following number on the blackboard: 2,159,301,271,000 and asked – Who can read this number? What does this number stand for?
(It was the number from the debt clock on the Internet and stands for the German national debt in May 2015.)
In groups they had to solve the following task:
Imagine all that money is laying in front of you in €100 bills. How big a surface would it cover? Think about a very big carpet of € 100 bills!
A €100 bill is 2.61inches by 6.14 inches.
If you laid out the bills side by side like a big carpet, what states would you be able to cover completely?

When you read this article, take the calculator and find out the correct result.

In the Workshop it was great fun and leaves impressive aha-experience among the students. specialy when they discovered that the carpet would cover 2/3 of whole germany.