From a class of $12$ girls and $18$ boys,two students are chosen randomly. What is the probability that both of them are girls?

$A$ card is drawn at random from a pack of $52$ cards. The probability that the drawn card is a court card,i.e.,a jack,a queen,or a king,is

Three dice are thrown. Find the chance of getting a sum of $16$.

There are three events $A, B, C$ one of which must and only one can happen. The odds are $8$ to $3$ against $A$ and $5$ to $2$ against $B$. Find the odds against $C$.

$A$ box contains $10$ identical electronic components,of which $4$ are defective. If $3$ components are selected at random from the box in succession,without replacement,what is the probability that exactly two components of the selected components are defective?

Study the given information carefully to answer the question that follows. An urn contains $4$ green,$5$ blue,$2$ red,and $3$ yellow marbles. If $8$ marbles are drawn at random,what is the probability that there are equal numbers of marbles of each colour?