Find the probability of the dart hitting the board in the circular region B (i.e. ring B)

Without calculating, write the percentage of probability of the dart hitting the board in circular region C (i.e. ring C).

From the given figure. Find the probability of the dart hitting the dart board in circular regions A.

What is the probability that a randomly thrown dart hits the square board in shaded region (Take π = (22)/(7) and express in percentage)

In a shooting test the probability of A,B,C hitting the targets are (1)/(2),(2)/(3)and(3)/(4) are respectively. If all of them first at the same target. Find the probability that i) Only one of them hits the target, ii) atleast one of them hits the target.

The probability that A hits a target is 1/4 and the probability that B hits the target is 1/3. If each of them fired once, what is the probability that the target will be hit atleast once.

The probability of a gun man hitting a target is 1/3, he fires ten shots, the random variable X is the number of hits. Find the mean and variance of X.

Three groups A, B, C are contesting for positions on the board of directors of a company. The probabilities of their winning are 0.5, 0.3 and 0.2 respectively. If the group A wins the probability of introducing a new product is 0.7 and the corresponding probabilities for group B and C are 0.6 and 0.5 respectively. Find the probability that the new product will be introduced.