Three vertices are chosen randomly from the seven vertices of a regular 7-sided polygon. The probability that they from the vertices of an isosceles triangle is-

Three vertices are chosen randomly from the seven vertices of a regular 7 -sided polygon. The probability that they form the vertices of an isosceles triangle is

Three vertices are chosen randomly from the seven vertices of a regular 7 -sided polygon. The probability that they form the vertices of an isosceles triangle is

Three vertices are chosen randomly from the seven vertices of a regular 7 -sided polygon. The probability that they form the vertices of an isosceles triangle is

Three vertices are chosen randomly from the seven vertices of a regular 7 -sided polygon. The probability that they form the vertices of an isosceles triangle is

Three vertices are chosen at random from the vertices of a regular hexagon then The probability that the triangle with these vertices is an equilateral triangle is equal to

Three vertices are chosen from the vertices of a regular hexagon,then the probability that they will form an equilateral triangle is

Three vertices are chosen at random from the vertices of a regular hexagon then The probability that the triangle has exactly two sides common with the side of the hexagon is

Three vertices are chosen at random from the vertices of a regular hexagon then The probability that the triangle has exactly one side common with the side of the hexagon is

Three vertices are chosen at random from the vertices of a regular hexagon then The probability that the triangle has exactly two sides common with the side of the hexagon is

Three distinct vertices are randomly chosen among the vertices of a cube. The probability that they from equilateral triangle is