The probability that a leap year will have $53$ Fridays or $53$ Saturdays is
$\frac{2}{7}$
$\frac{3}{7}$
$\frac{4}{7}$
$\frac{1}{7}$
An anti aircraft gun take four shots at an enemy plane moving away from it. The probability of hitting the plane at the first, second, third and fourth shot are $0.4, 0.3, 0.2$ and $0.1$ respectively. The probability that the gun hit the plane is :-
An experiment consists of recording boy-girl composition of families with $2$ children. What is the sample space if we are interested in the number of girls in the family?
Five horses are in a race. $Mr. \,A$ selects two of the horses at random and bets on them. The probability that $Mr.\, A$ selected the winning horse is
In each of the following experiments specify appropriate sample space A person is noting down the number of accidents along a busy highway during a year.
A single letter is selected at random from the word “$PROBABILITY$”. The probability that the selected letter is a vowel is