Urgent!!How the Calculation Appears when running the report for Survey!!

Hi

I have a doubt..for survey report

U have a Product, Product type,Customer No,Survey Questions,score & Average per Customer

So when U calculate the average based on the customer responded for the survey..

Will the initail view of the report ie when u run the query....gives u the Different Score Calculation ....becoz u calculate average per Product,per customer,per product type ..

But when I filter down based on the customer or product etc....I get the correct average score....without filtering as per user requirement for the initial view....average score give total of all the questions...

Give some Ideas...whether amm I going in wrong path..

Thanks

BI Learner