This week the question is: Can You Catch the Breakaway?
This time around, a lone rider in the Tour de Fiddler is being pursued by a group of four riders. The four riders have an advantage—they take equal turns being in the lead position, while the other three riders draft behind. At any given speed, being in the lead position (as well as riding solo) requires twice as much power as drafting.
Assume that every rider must maintain the exact same average power over time, whether they are the lone rider or in the pack of four. To be clear, their power can change over time, but the time-averaged value must be the same for every rider. Also, when leading a pursuing group or riding solo, one’s speed is directly proportional to one’s power. When drafting, one’s speed matches that of the leader (again, at half the power output).
The pursuers just passed under a banner indicating there are 10 kilometers left in the stage. How far back of the lone rider can they afford to be, such that they still catch them at the finish line
And for extra credit:
In today’s stage of the Tour de Fiddler, there are 176 total riders. Some riders are grouped together in a single breakaway, while the remainder are grouped together in the peloton.
The breakaway group is 10 kilometers from the finish, while the peloton is one kilometer behind (i.e., 11 kilometers from the finish).
As before, assume that every rider must maintain the exact same time-averaged power when leading a group, and that drafters can match the leader’s speed but with half the power.
What is the smallest number of riders that the breakaway needs to reach the finish line before the pursuing peloton
Solutions:
Calculation sheet 1. Including answer.
And for extra credit:
Calculation sheet 1 and 2. Sheet 2 includes the answer, which has to be rounded to: (highlight to reveal)
10.
Stuff from ommadawn.dk (Lise Andreasen) 
