(Solved): Four cubes with written six digits on their walls 1, 2, 3, 4, 5, 6 and a regular tetrahedron wit ...

Four cubes with written six digits on their walls – 1, 2, 3, 4, 5, 6 and a regular tetrahedron with written four digits on their walls - 1, 2, 3, 4 are given. In random way one of these graphical figures is chosen and after that it is thrown down. After the chosen figure is thrown down it turns out that the digit 3 occurs. Find the probability that the chosen body is a cube.