jcnissi wrote:Please help me solve this:
Of the 100 pet owners who respond to a survey, 50 own cats, 42 own dogs, and 7 own both. How many respondents own neither a cat nor a dog?
a. 7
b. 8
c. 10
d. 12
e. 15
In words rather than symbols:
True # of items = (total # in group 1) + (total # in group 2) + (# in neither) - (# in both groups)
or, more simply:
True # = G1 + G2 + neither - both
In this question:
True # = 100
Cats = 50
Dogs = 42
Both = 7
So:
100 = 50 + 42 + neither - 7
100 = 85 + neither
15 = neither... choose (E).
