500 20s.
20s is correct.
7.5
120
4
10.3
400 ÷ 20 = 20
5.4 or 5 with a remainder of 8.
320
40
50 billion of them.
A monthly income like that was HUGE back in the 20s. Especially because of prohibition. 1000 dollars was almost as much as the annual income.