Mixture Problem Rate (mph) D(11"::iT-laensc)e First part of race Last part of race Cannot be found by Totals for adding the entire race two averages above! 2.The Daytona 500 started in 1959 with an average speed of 135 mph but before they raced on the big speedway they would race up and down on the beach. In 1954 Lee Petty raced on the beach for a total 160 miles. As the 2 hour race developed Lee averaged 90 mph for the first part of the race but only 60 mph for last part. How long did he race at 90 mph and how long at 60 mph? Rate (mph) - Time (hours) = Let F represent the hours he raced at 90 mph. Let L represent the hours he raced at 60 mph. Complete the chart below using information from the problem. Ute the formula to work across and complete any empty spaces in the last column