A 1-dollar bill is 6.14 inches long, 2.61 inches wide, and 0.0043 inch thick.

Assume your classroom measures 23 by 29 by 13 ft. How many such rooms would a billion 1-dollar bills fill? (Round your answer to one decimal place.)

The area of the classroom is 8,671 in squared. you get this by multiplying base x height x width. You plug the same formula into the dollars he mentions and get 0.06890922 in squared. Than you divide the classroom dimensions by the dollar dimentions. that's 8,671 : 0.06890922 = 125,832.21809795. rounding that to one decimal place, it would take $125,832.2 to fill up the classroom. (I might have gotten this wrong but I think this is the answer)