Q:

The probability that a comic book reader in a particular city prefers comics published by Company A is 25%. The probability that a comic book reader in the city is male is 70%. If the probability of a comic book reader in the city being a male, given that the reader prefers Company A's comics, is 40%, what is the probability of the reader preferring Company A's comics, given that the reader is a male? 0.14 0.25 0.30 0.45

Accepted Solution

A:
We know that 70% of all comic book fans are male, and that 40% of Company A fans are male. 

Since 25% of all comic book fans are company A fans: 
0.4 * 0.25 (meaning 40% of 25%) = 0.1, or 10% of all comic book fans are male company A fans. 

What percentage, then, of male comic book fans are company A fans?
0.1 ÷ 0.7 = 0.142
We divide 10%, the percentage of all comic book fans that are male and company A fans, by the percentage of comic book fans that are male, since we are given that the fan is male. 

Answer is 0.14