Final answer:
To estimate the lap time for Marsha's eight-year-old son, use the line of best fit equation to find the corresponding value for an age of eight years.
Step-by-step explanation:
To estimate the length of time it should take Marsha's eight-year-old son to run one lap, we can use the line of best fit created by recording the time it took six children of different ages to run one lap around the track. The line of best fit helps us determine the average relationship between age and lap time. We can plug in the age of Marsha's eight-year-old son into the equation of the line of best fit to find the corresponding estimated lap time.
For example, let's say the equation of the line of best fit is y = 2x + 5, where x represents the age of the child and y represents the time in seconds to run one lap. If Marsha's eight-year-old son has an age of x = 8, we can substitute this value into the equation:
y = 2(8) + 5 = 16 + 5 = 21 seconds.
Therefore, the estimated lap time for Marsha's eight-year-old son would be approximately 21 seconds.