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Seems Simple Enough...HELP!

An auto race is taking place on a circular track. The total number of cars in the race is 1/3 of the number of cars in front of the red car, plus 3/4 of the number of cars behind the red car. How many cars are in the race?

Can you solve this? If so, I need your help....what is your reasoning?

Some key "personal" concerns:
  • On a circular track, doesn't the number of cars in front of a car equal the number of cars behind a car?
  • On a circular track, is the red car also behind itself...or in front of itself?
  • If you view the cars in front or behind the red car as being two separate (non-overlapping groups), the number of cars becomes a negative value?
  • The problem must be do-able, given its source and intended level!
HELP!...Or it will be a long summer!


Source: MacMillan Math : Grade 7, 1987, p. 245

Hint: How can I provide a hint, when I need help with the problem itself....


Solution Commentary: Even if the red car is the only car on the track, the problem still is impossible...!