Question 472851
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Hi,
The Wildlife Federation surveyed 220 San Diego residents. The results are as follows:
32 had a membership to the Birch Aquarium
57 had a membership to the San Diego Zoo
21 had both
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i. How many had only a zoo membership? 57-21 = 36
ii. How many had only an aquarium membership? 32-21 = 11
iii. How many belonged to either one or the other or both? 36 + 11 + 21 = 68
iv. How many belonged to neither? 220 - 68 = 152