11. A card is drawn at random from a well shuffled pack of 52 cards. Find the probability that the card will be black or face cards
13. One card is drawn at random from the number cards numbered from 10 to 21 . Find the probability that the card may be prime or even numbered card
14. Define sample space. What is the probability of a certain event?
15. A die is rolled once. What is the probability that the digit turn off is a prime number.
16. A bag contains a dozen of identical balls. Among them, 3 are red, 5 are greed and the rest are white. If a ball is randomly drawn, what is the probability of getting the white ball?
17. A card is drawn at random from a well shuffled pack of 52 cards. Find the probability that the card will be black king or red queen.
18. Three athletes A, B and C are to run a race. If A is twice as likely to win B and B is thrice as likely to win C. Find the probability of each athlete winning.