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
$\frac{2}{5}$
$\frac{1}{3}$
$\frac{7}{20}$
$\frac{3}{10}$
Let a biased coin be tossed 5 times. If the probability of getting 4 heads is equal to the probability of getting 5 heads, then the probability of getting atmost two heads is
A pair of fair dice is thrown independently three times. The probability of getting a score of exactly $9$ twice is
Two numbers $a$ and $b$ are chosen at random from the set of first $30$ natural numbers. The probability that ${a^2} - {b^2}$ is divisible by $3$ is
Two cards are drawn at random from a pack of $52$ cards. The probability that both are the cards of spade is
A three digit number is formed by using numbers $1, 2, 3$ and $4$. The probability that the number is divisible by $3$, is