Cabbage heads for Cole Slaw???

[bbq.tom]

Anyone know approximately how many heads of cabbage I should get to make enough Cole slaw for 400 servings? I'm assuming that a serving size will be approximately 3 oz., and that the average head of cabbage that I can get right now is approximately 8" diameter (summer 10"-12" heads would be NICE, but alas, I've got to use what I can get!).

Any assistance would be greatly appreciated!!!

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