Final answer:
To calculate the equation of the least-squares regression line, first calculate the slope using the correlation, standard deviations of x and y values, then calculate the y-intercept using the mean values and slope.
Step-by-step explanation:
To calculate the equation of the least-squares regression line, you can use the formula: y = a + bx
Where 'b' is the slope of the line, and 'a' is the y-intercept. The slope 'b' can be calculated using the correlation (r), the standard deviation of the y values (Sy), and the standard deviation of the x values (Sx) as follows: b = r(Sy/Sx)
The y-intercept 'a' can be found using the means of the x and y values (μx and μy) and the slope 'b'
a = μy - bμx
Given the summary statistics, the slope 'b' is: b = 0.59(7.1/3.29)
And the y-intercept 'a' is: a = 45.3 - b(78.9)
After calculating 'b' and 'a', plug these values into the regression line formula to obtain the final equation. To ensure accuracy in the calculations, all figures should be rounded to two decimals as the final step.