Question
There are 20 bikes in spinning class, the bikes are arranged 4 rows, with 5 bikes in each row. They hope to be in the same row, but cannot request specific bike. Determine the probability that all 5 friends will be in same row with Jeff and dariya at either end.
Answers
Reiny
At the ends it could be Jeff, Dariya or Dariya, Jeff
So for the first row:
2x3x2x1 or 12 ways, leaving 15! for the other positions.
but there are 4 rows,
prob(of your event) = 4x12(15!)/20! = .000025799
So for the first row:
2x3x2x1 or 12 ways, leaving 15! for the other positions.
but there are 4 rows,
prob(of your event) = 4x12(15!)/20! = .000025799