A health inspector wants to check compliance with a new city ordinance on meat storage. Since he can only inspect 10 of the 33 stores, he chooses to do a stratified random sample that consists of all 3 of the large chain stores, 4 of the 10 smaller chain stores, and 3 of the 20 locally-owned stores.

From his inspection he finds that 2 of the 3 large chain stores are compliant, 1 of the 4 smaller chain stores is compliant, and 1 of the 3 locally-owned chain stores is compliant.

Using the sample results, estimate the proportion of the entire population of stores that is compliant with the ordinance.
A) 0.121
B) 0.4
C) 0.6
D) 0.879

I think it C.

(2+1+1)/(3+4+3) = ?