Question

The scatter plot shows the winning times, in minutes, in a track event over eight consecutive years.

Scatter plot with x axis labeled Time in Years and y axis labeled Winning Time, with points at 1 comma 5 and 4 tenths, 2 comma 5, 3 comma 4 and 6 tenths, 4 comma 4 and 9 tenths, 5 comma 4 and 1 tenth, 6 comma 3 and 9 tenths, 7 comma 3 and 6 tenths, and 8 comma 3 and 3 tenths.

Predict the winning time in year 11 of the race.

1.37 minutes
1.63 minutes
2.45 minutes
2.98 minutes

Answer 1

The equation of the line of best fit obtained from the using MS Excel indicates that the predicted winning time in year 11 of the race is about 2.45 minutes

The steps used to predict the winning time in year 11 is as follows;

The points on the scatter plot are; (1, 5 4/10), (2, 5), (3, 4 6/10), (4, 4 9/10), (5, 4 1/0), (6, 3 9/10), (7, 3 6/10), and (8, 3 3/10)

The above data for the Winning time and time in years can be plotted using MS Excel to get the equation of the line of best fit as follows;

y = -0.2929·x + 5.6679

The above equation indicates that the when the time in years is 11 year, we get;

y = -0.2929 × 11 + 5.6679

y ≈ 2.45

Therefore, the predicted winning time in year 11 is about 2.45 minutes