A state fair wants to use third degree price discrimination to establish their admission fees.The fair's marginal cost is $5 per person.Marketing consulting firm has estimated that the own price elasticity of demand for adults is -1.75, the own price elasticity for students is -2.25, and the own price elasticity of demand for senior citizens is -3.2.

If the fair practiced third degree price discrimination, how much should they charge senior citizens?Round to the nearest whole number.