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The standard 26-mile, 385-yard marathon dates to 1908, when the Olympic marathon started at Windsor Castle and finished before the Royal Box at London’s Olympic Stadium. Today’s top marathoners achieve times around 2 hours, 3 minutes for the standard marathon, (a) What’s the average speed of a marathon run in this time? (b) Marathons before 1908 were typically about 25 miles. How much longer does the race last today as a result of the extra mile and 385 yards, assuming it’s run at part (a)’s average speed?
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