The thickness of a dictionary was 1/8

Question

of the height of a table.
height of 3 such tables when stacked on top of one another was 21/8
What is the total thickness of 2 such dictionaries?

Answer 1

Height of 3 tables = 21/8
so height of 1 table = 7/8

so thickness of 1 dictionary = (1/8)(7/8) = 7/64
so 2 dictionaries ----> 7/32 , whatever units you have

Weird question!