Two tables, same structure. Need to SUM and GROUP data from each table.

[kutyadog]

I have two tables containing football passing information.
The structure for both tables is exactly the same.

table1
passnum, receiver, yards_gained, quarter

table2
passnum, receiver, yards_gained, quarter

I want to write a single query that will allow me to give the SUM and AVG for yards_gained GROUPed by each quarter... such as below:

quarter, total yards, avg yards per play
1, 584, 12.3
2, 612, 13.1
3, 490, 9.3
4, 544, 10.5
OT, 89, 7.7

I have been trying to write this for two days now with little progress. Any help is greatly appreciated.

[laserlight]

What have you tried, and why are those two tables not combined into one?