To complete 9 laps of a seven-mile track, Brian needs to cover a distance of 63 miles (9 laps x 7 miles/lap).
To qualify, he needs to do this at an average speed of 114.78 mph.
So, the total time he needs to complete the race is:
63 miles ÷ 114.78 mph = 0.549 hours
To find the time needed to complete the remaining 6 laps (since he has already completed 3), we can subtract the time he has already taken from the total time needed:
Total time needed - Time taken = Time needed to complete remaining laps
0.549 hours - (3 laps ÷ 92 mph) = Time needed to complete remaining laps
0.549 hours - 0.03261 hours = 0.51639 hours
Converting this to seconds:
0.51639 hours x 3600 seconds/hour = 1858.004 seconds
Therefore, approximately 1858 seconds (or about 31 minutes) will be needed for Brian to finish the race and qualify.
Brian is trying to qualify for a race. A driver needs to complete 9 laps of a seven-mile track at an average speed of 114.78 mph to qualify. Brian has already completed the first three laps. His average speed so far is ninety-two mph. Approximately how many seconds will Brian need to finish the race to qualify?
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