Bunuel wrote:
At an event, 40% of the attendees are over 50 years old and another 20% are under 20 years old. Which of the following statements must be true?
I. The ratio of those over 50 to those between 20 and 50 inclusive is 2 : 3.
II. The ratio of those under 20 to those between 20 and 50 inclusive is 1 : 2.
III. 1/3 of the attendees who are not over 50 are under 20.
A. I only
B. I and II only
C. I and III only
D. II and III only
E. I, II and III
let total = 100
so >50 ; 40
<20 ; 20 and b/w 20
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