Suppose a random sample of 10,000 individuals are asked to identify their favorite brand of soap among ten choices. The following results from the survey are obtained.
Brand Observed Frequency
A 1200
B 900
C 850
D 1160
E 1020
F 975
G 1100
H 980
I 1035
J 780
Please help me to Test the hypothesis of the preferences for each brand where they are equal (uniform). Test this at the 0.05 level.