Question

If someone tells you that the U.S. public debt is 1.258 x 10^13 dollars, how much money is that?

Answer 1

12,580,000,000,000

Answer 2

http://www.wolframalpha.com/input/?i=12%2C580%2C000%2C000%2C000

Answer 3

look up a table of zeros. 6 is a million, 9 is a billion, and 12 is a trillion. Since you have 13 zeros, move the decimal place over to the right in scientific notation to lower the exponent.

12.58 x 10^12

so that would be 12.58 trillion dollars or 12 trillion, 580 billion.