Summarizing two different tables

Hi there,

I have two tables in my data model that contain marketing costs for our organisation. I would like to combine them into one table and summarize the cost per day. As both tables are different, i can't merge the queries (and i also would like to retain the individual tables).

Example:

Table A has marketing costs for 1/1, 2/1 and 4/1 for let's say 10 euro each.

Table B has marketing costs for 2/1, 3/1 and 5/1 for 10 euro each

Table C (the designated new table) would have:
1/1: 10

2/1: 20

3/1: 10

4/1: 10

5/1: 10

Can anyone explain me how to do that? 

Thanks!

David