4.23 Do Americans prefer Coke or Pepsi? A survey was con-ducted by Public Policy Polling (PPP) in 2013; the results were as follows:

a. Given that an American is a male, what is the probability that he prefers Pepsi?

b. Given that an American is a female, what is the probability that she prefers Pepsi?

c. Is preference independent of gender? Explain.

GENDER PREFERENCE Coke Pepsi Neither/Unsure Total Source: Data extracted from "Public Policy Polling" Report 2013, bit.ly/YKXfzN Female Male Total 215 175 110 500 120 95 65 95 80 45 280 220 220