SOLUTION: The Wildlife Federation surveyed 140 San Diego residents. The results are as follows: 22 had a membership to the Birch Aquarium 26 had a membership to the San

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Question 259063: The Wildlife Federation surveyed 140 San Diego residents. The results are as follows:

22 had a membership to the Birch Aquarium
26 had a membership to the San Diego Zoo
15 had both

Construct a Venn diagram
Answer the following questions:

i. How many had only a zoo membership?
ii. How many had only an aquarium membership?
iii. How many belonged to either one or the other or both?
iv. How many belonged to neither?
Found 2 solutions by drk, richwmiller:
Answer by drk(1908) (Show Source):
You can put this solution on YOUR website!
First draw 2 overlapping circles call the left circle aquarium and the right zoo.
Second, draw small horizontal lines in each of the three regions and also one on the outside right of the diagram.
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step 1 - "15 had both" means put 15 into the overlapping region shared by both.
step 2 - "22 had a membership to the Birch Aquarium" means that 15 + x = 22 - > so x = 7. Put a 7 on the aquarium line.
step 3 - "26 had a membership to the San Diego Zoo" means 15 + y = 26 - -> so y = 11. Put an 11 on the zoo line.
step 4- there is only one line left, the outside. "140 San Diego residents" means that all lines of information must add to 140. We have 7 + 15 + 11 + z = 140 - -> z = 107. Put a 107 on the outside line.
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i. How many had only a zoo membership? this is y, so 11
ii. How many had only an aquarium membership? this is x, so 7
iii. How many belonged to either one or the other or both? this is 15 + 7 + 11 = 33
iv. How many belonged to neither? this is z, so 107

Answer by richwmiller(17219) (Show Source):
You can put this solution on YOUR website!

26-15=11
11 had only zoo
22-15=7
7 had only aquarium
7+15+11=33
33 belonged to one or both
140-33=107
107 belonged to neither