Categorized Expense Report Reference

For one of my classes I had to create an expense report. Each expense had to be categorized, and then I have to summarize the amount I spent on each Category.
I used an excel table to create the report.
It looks kind of like this,
---------------------------------------------------------------
Date |Location|Item|Total |Category|Category Reference Number
-----|--------|-----|------|---------|---------------------------|
3/27 |I-HOP |Food |$5.00 |Going out| 8
-----|--------|-----|------|---------|---------------------------
3/31 |Walmart|Gum |$2.99 |Misc |2
-----|--------|-----|------|---------|---------------------------

Is there a formula that I could use to give me a total spent on a category based on the category name or the reference Number?

Look into SumIf Function

http://www.techonthenet.com/excel/formulas/sumif.php