An urn contains $6$ blue,$4$ red,$3$ green,and $2$ yellow marbles. If three marbles are picked at random,what is the probability that $2$ are red and $1$ is green?

Out of $40$ consecutive natural numbers,two are chosen at random. The probability that the sum of the numbers is odd is:

Two cards are drawn successively with replacement from a pack of $52$ cards. The probability of drawing two aces is

Ten students are seated at random in a row. The probability that two particular students are not seated side by side is

$A$ draws two cards with replacement from a pack of $52$ cards and $B$ throws a pair of dice. What is the chance that $A$ gets both cards of the same suit and $B$ gets a total of $6$?

$A$ problem in Statistics is given to four students $A, B, C$ and $D$. Their chances of solving it are $\frac{1}{3}, \frac{1}{4}, \frac{1}{5}$ and $\frac{1}{6}$ respectively. What is the probability that the problem will be solved?