Six points are there on a circle . Two triangles are drawn with no vertex common. What is the probability that none of the sides of the triangles intersect
$\frac{2}{5}$
$\frac{1}{3}$
$\frac{7}{20}$
$\frac{3}{10}$
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
A bag contains $3$ white and $5$ black balls. If one ball is drawn, then the probability that it is black, is
Two numbers $x$ and $y$ are chosen at random from the set of integers $\{1,2,3,4......15\}.$ The probability that point $(x,y)$ lies on a line through $(0,0)$ having slope $\frac{2}{3}$ is
The probability that the three cards drawn from a pack of $52$ cards are all red is
$4$ cards are drawn from a well-shuffled deck of $52$ cards. What is the probability of obtaining $3$ diamonds and one spade?