Well one mole of nickels is 6x10^23 or 3x10^24 cents. To make this in dollars, divide by 100 or lower the exponent by two and get 3x10^22. 7.1 billion is the same as 7.1x10^9 so take 3x10^22 divided by 7.1x10^9 and get 4x10^14 which is $400,000,000,000,000 per person. Someone please correct me if I'm wrong :)