Dear Experts.

Our lecturer gave us a customer satisfaction survey output from restaurants chain; the data contain 3 variables only.
1-Branch code: A, B, C, E and D.
2-Meal Type: Breakfast, Lunch and Dinner.
3-Type of Complaint: Friendly service, Relaxing atmosphere, Timely service, Daily Special, Meal Appearance and Food.
Also I have the number of Complaints from Jan-2004 till Sep-2005, but it is unclassified according to the data above.
First I will try to see if the rate of complaints varies based upon branch or meal type against the type of complaint.
The sample size is 156, classified within the branches as below.
E=47, D=46, B=25, C=22 and A=16. No equality.
My question is, are the results will be biased because 60 % from the data came from E and D only?
Also with respect to the meal type 45% from the data represent the lunch meal.
Shall I continue?

Thanks.
Al Obaidi.