The paper Effects of Age and Gender on Physical Performance (Age [2007]: 7785) describes a study of

Question:

The paper €œEffects of Age and Gender on Physical Performance€ (Age [2007]: 77€“85) describes a study of the relationship between age and 1-hour swimming performance. Data on age and swim distance for over 10,000 men participating in a national long-distance 1-hour swimming competition are summarized in the accompanying table. In Exercise 5.34 from Section 5.3, a plot of the residuals from the least-squares line showed a curved pattern that suggested that a quadratic curve would do a better job of summarizing the relationship between x = representative age and y = average swim distance. Find the equation of the least-squares quadratic curve and use it to predict average swim distance at 40 years of age. y^ = 3843.027 + 10.619x - 0.360x2 y^ = 3691.293