Three coins are tossed together, then the probability of getting at least one head is

If a dice is thrown twice, then the probability of getting $1$ in the first throw only is

Two coins are tossed. Let $A$ be the event that the first coin shows head and $B$ be the event that the second coin shows a tail. Two events $A$ and $B$ are

Three letters are to be sent to different persons and addresses on the three envelopes are also written. Without looking at the addresses, the probability that the letters go into the right envelope is equal to

One card is drawn from each of two ordinary packs of $52$ cards. The probability that at least one of them is an ace of heart, is

Out of $60 \%$ female and $40 \%$ male candidates appearing in an exam, $60\%$ candidates qualify it. The number of females qualifying the exam is twice the number of males qualifying it. A candidate is randomly chosen from the qualified candidates. The probability, that the chosen candidate is a female, is.