I have a word problem that is asking me for the amount of sales for the past year starting from 3Q09.

With that being said would the past year from 3q09 look like this:
3q09
2q09
1q09
4q08

This example has 4 quarters which = one year

or this

3q09
2q09
1q09
4q08
3q08

This example has 5 quarters but its from 3q09 to 3q08 which is also a year.

Im confused.

Since there are two "third quarters" included in the second case, it actually represents three months more than one year.

Gotcha, thanks for clarifying I thought

3q09
2q09
1q09
4q08

was correct!