Entry slip (Sep 25.)---Babylonian Table of Multiplying to 45

 

Class notes:

What might these tables mean?
The first column multiplied by the second column equals 60. Or, 1/2 = 30/60, 1/3 = 20/60, ...1/10=6/60, this is a table of unit fraction. 
Note that, in this notation, commas separate place values (for both whole numbers and fractions).

Can you figure out the common theme here?

Why are certain numbers missing from the left hand column? For example, there is no 7, 11, 13, etc.
Because 60 divided by these numbers will get recurring decimal numbers. 
How do fractions in the Babylonian style connect with our fractions? (Keep this in mind as we learn about ancient Egyptian fractions later on...)