Problems

Age
Difficulty
Found: 2

The frog jumps over the vertices of the hexagon \(ABCDEF\), each time moving to one of the neighbouring vertices.

a) How many ways can it get from \(A\) to \(C\) in \(n\) jumps?

b) The same question, but on condition that it cannot jump to \(D\)?

c) Let the frog’s path begin at the vertex \(A\), and at the vertex \(D\) there is a mine. Every second it makes another jump. What is the probability that it will still be alive in \(n\) seconds?

d)* What is the average life expectancy of such frogs?

A high rectangle of width 2 is open from above, and the L-shaped domino falls inside it in a random way (see the figure).

a) \(k\) \(L\)-shaped dominoes have fallen. Find the mathematical expectation of the height of the resulting polygon.

b) \(7\) \(G\)-shaped dominoes fell inside the rectangle. Find the probability that the resulting figure will have a height of 12.