Tamil Nadu Board Solutions for Chapter: Statistics And Probability, Exercise 11: Exercise 8.3

If$A$ is an event of a random experiment such that $P\left(A\right) : P\left(\overline{A}\right)=17:15$ and $n\left(S\right)=640$, then find $n\left(A\right)$.

 A coin is tossed thrice. What is the probability of getting two consecutive tails? 

 Two unbiased dice are rolled once. Find the probability of getting the sum as $1$.

In a box, there are $20$ non-defective and some defective bulbs. If the probability that a bulb selected at random from the box found to be defective is $\frac{3}{8}$ then, find the number of defective bulbs. 

The king and queen of diamonds, queen and jack of hearts, jack and king of spades are removed from a deck of $52$playing cards and then well shuffled. Now one card is drawn at random from the remaining cards. Determine the probability that the card is a queen of a red card.

In a game, the entry fee is $₹150.$ The game consists of tossing a coin $3$ times. Dhana bought a ticket for entry. If one or two heads show, she gets her entry fee back. If she throws $3$ heads, she receives double the entry fees. Otherwise, she will lose. Find the probability that she gets double entry fee.

In a game, the entry fee is $₹150.$ The game consists of tossing a coin $3$ times. Dhana bought a ticket for entry. If one or two heads show, she gets her entry fee back. If she throws $3$ heads, she receives double the entry fees. Otherwise, she will lose. Find the probability that she just gets her entry fee, in the lowest fraction form.

In a game, the entry fee is $₹150.$ The game consists of tossing a coin $3$ times. Dhana bought a ticket for entry. If one or two heads show, she gets her entry fee back. If she throws $3$ heads, she receives double the entry fees. Otherwise, she will lose. Find the probability that she loses the entry fee.