Answer:
4 napkins on each table.
Explanation:
First, we need to figure out how many napkins he put in the 4 tables after he put his napkins on 6 tables.
124 - 108 = 16
He put 16 napkins on 4 tables. Now divide 16 by 4.
16 / 4 = 4 napkins.
He put 4 napkins on each table.