Two dice are thrown simultaneously. The probability of obtaining a total score of $5$ is

The probability that a person $A$ completes a work in a given time is $\frac{2}{3}$ and the probability that another person $B$ completes the same work in the same time is $\frac{3}{4}$. If both $A$ and $B$ start doing this work at the same time,then the probability that the work is completed in the given time is

$2$ boys and $2$ girls are in Room $X$,and $1$ boy and $3$ girls are in Room $Y$. Specify the sample space for the experiment in which a room is selected and then a person.

Two unbiased dice are thrown. Then the probability that neither a doublet nor a total of $10$ will appear is

Three coins are tossed once. Find the probability of getting $2$ heads.

When two dice are thrown, the probability of getting an ordered pair $(x, y)$ such that $x^2+y^2 \leq 25$, where $x$ and $y$ are the numbers that show up on the two dice, is: