examday

tmua.me papers

tmua.me Extreme Set B Paper 2 · Q7

Paper 2ProbabilityStatistics

Initially the six numbers 1,2,3,4,5,61,2,3,4,5,6 are written on a board.

In each move, one of the current entries is chosen uniformly at random and erased. Every other entry is then replaced by its arithmetic mean with the erased entry. This is repeated until only one entry remains.

What is the probability that the final entry is exactly 22?

A1360\dfrac1{360}
B1180\dfrac1{180}
C1120\dfrac1{120}
D160\dfrac1{60}
E130\dfrac1{30}
F115\dfrac1{15}

Read the questions freely. Sign in to check your answer, see the worked solution and save your progress.

Sign in to check your answerPractise the whole paper →