Real-Life Math -- Solution
To find the racer's speed per mile, you must first convert hours and minutes into minutes, then divide the number of miles traveled by the number of minutes each race took.
That will give you the racer's speed per minute for each of the races. Then multiply that number by 60 (the number of minutes in an hour) to give you the speed in miles per hour.
Race 1
9 hours x 60 = 540 minutes 540 minutes + 45 minutes = 585 minutes
125 miles / 585 minutes = 0.21 miles per minute
0.21 x 60 = 12.6 miles per hour
So, cyclist Mike Carmichael rode at a speed of 12.6 miles per hour in Race 1.
Race 2
9 hours x 60 = 540 minutes 540 minutes + 28 minutes = 568 minutes
125 miles / 568 minutes = 0.22 miles per minute
0.22 x 60 = 13.2 miles per hour
Carmichael road at a speed of 13.2 miles per hour in Race 2.
To determine the difference in speed between the 2 races, subtract Race 1 from Race 2:
13.2 - 12.6 = 0.6
Carmichael rode 0.6 miles per hour faster in Race 2 than he did in Race 1.
As a pro racer, you'll be keeping a chart of your "times" (that is, your speed). This chart can be used as a benchmark for fitness levels. Racers can adjust their focus in training depending on how they are doing on their speed.
Keeping track of your speed is really more of a training tool than a way to build a racing strategy. That's because neither you, your teammates nor the competition will always race at the same speeds. And you don't know what the difference will be until the race happens.
You just have to push yourself to train harder and more effectively, and hope your body is up to the test.