Christina can paint a chair in 3 hours, and Victoria can paint a chair in 5 hours. How many hours will it take to paint the chair when the two girls work together? Write an equation that could be used to model this problem. Let t represent the time (in hours) that it will take to paint the chair when the two girls work together. An equation that could be used to model this problem is D (Use integers or fractions for any numbers in the equation.)