Check Your Concept

 

Check your concept of chapter Probability by solving these conceptual questions

PRACTICE QUESTIONS BASED ON EXERCISE 15.1

1. Write the name of the experiment whose outcomes has to be among the set of the events that are completely known but whose exact outcome is unknown.

2. A fair dice is rolled. What is the probability of getting number x such that 1 ≤ x ≤ 6.

3. For an event A, find P(A) + P(not A).

4. A man is known to speak truth 5 out of 7 times. He throws die and a number other than six comes up. Find the probability that he report it is a six.

5. A man is know to speak truth 5 out of 6 times. He draws a face card from a pack of 52 playing cards. Find the probability that he reports it is a six.

6. The probability of getting a bad egg in a lot of 800 egg is 0.125. Find the number of bad egg in the lot.

7. The probability of getting a bad pen in a lot of 400 pens is 0.25. Find the number of good pen in the lot

8. Archana calculate that probability of her winning the first prize in a lottery is 0.04. If 12000 tickets are sold, how many tickets has she bought?

9. A card is drawn at random from a well shuffled pack of 52 playing cards. Find the probability of getting a red face card.

10. A die is thrown once. What is the probability of getting a number greater than 4?

11. One card is drawn from a pack of 52 cards, each of the 52 cards being equally likely to be drawn is an arc.

12. A bag contains 3 red balls, 5 black balls and 4 white balls. A balls is drawn at random from the bag. What is the probability that the ball is white?

13. A letter is chosen at random from the letters of the word ‘ASSASSINATION’ Find the probability that the letter chosen is a vowel?

14. One card is drawn from a well-shuffled deck of 52 cards. Find the probability of getting the jack of hearts.

15. Two players, Sangeeta and Reshma, play a tennis match. It is know that the probability of winning the match by Sangeeta is 0.62. what is the probability of winning the match by Reshma?  

16. Fill in the blanks:

1. Probability of a sure event is…..

2. Probability of an impossible event is….

3. The probability of an event (other than and sure impossible event) lies between….

4. A die is rolled once. The probability of getting a prime number is…..

17. A letter of English alphabet is chosen at random. Determine the probability that the chosen letter is  a consonant.

18. A game of chance consist of spinning an arrow which comes to rest pointing at one of the numbers 1, 2, 3, 4, 5, 6, 7, 8 and these are equally likely outcomes. Find the probability that the arrow will point at any factor of 8.

19. The king, queen and jack of diamonds are removed from a pack of 52 cards and then the pack is well-shuffled. A card is drawn from the remaining cards. Find the probability of getting a cards of (i) diamonds, (ii) a jack.

20. A tickets is drawn at random from a bag containing tickets numbered from 1 to 40. Find the probability that the selected ticket has a number which is a multiple of 5.

21. Three cards of spades are lost from a pack of 52 playing cards. The remaining cards were well-shuffled and then a card was drawn at random from them. Find the probability that the drawn cards is of black colour.

22. Two different dices are tossed together. Find the probability 

1. That the number on each dice is even

2. That the sum of numbers appearing on the dice is 5.

23. Find the probability that a leap year should have exactly 52 Tuesday.

24. A card is drawn at random from a well-shuffled deck of playing cards. Find the probability that the card drawn is

1. A card of spade or an ace

2. A red king

3. Neither a king nor a queen

4. Either a king or a queen

25.  Cards marked with numbers 3, 4, 5,……..50 are placed in a box and mixed thoroughly. One cards is drawn at random from the box. Find the probability that number on the drawn cards.

1. Divisible by 7.

2. A number which is a perfect square 

26. All the three face cards of spades are removed from a well-shuffled pack of 52 cards. A cards is that drawn at random from the remaining pack. Find the probability of getting 

1. A black face card,

2. A queen,

3. A black card.

27. The king, queen and jack of clubs are removed from a deck of 52 cards and the remaining cards are shuffled. A cards is drawn from the remaining cards. Find the probability of getting a card of

1. Heart

2. Queen

3. clubs

28. Cards bearing number 1, 3, 5, ……….., 35 are kept in a bag. A card is drawn at random from the bag. Find the probability of getting a card bearing

1. A prime number less than 15.

2. A number divisible by 3 and 5.

29. Two dice are rolled once. Find the probability of getting such numbers on the two dice, whose product is 12.

30. All kings, queens and aces are removed from a pack of 52 cards. The remaining cards are well-shuffled and then cards is drawn from it. Find the probability that the drawn card is 

1. A black face card

2. A red card.

31. A bag contains 5 red balls, 8 white balls, 4 green balls and 7 black balls. If one ball is drawn at random, find the probability that it is (i) black (ii) red (iii) nit green.

32. A bag contain 12 ball out which x are white.

1. If one ball is drawn at random, what is the probability that it will be a white ball?

2. If 6 more white balls are put in the bag, the probability of drawing white ball will be double than that in (i). find x.  

33. The probability of selecting a red ball at random form a jar that contains inly red, blue and orange balls is 14. The probability of selecting a blue ball at random from the sane jar is 13. If the jar contains 10 orange balls, find the total number of balls in the jar.

34. A bag contains 18 balls out of which x balls are red.

1. If one ball is drawn at random from the bag, the probability of drawing a red ball will be 98 times the probability of drawing a red ball in the first case. Find the value of x.

35. A bag contains 24 balls out of which x are white. If one ball is drawn at random the probability of drawing a white ball is y. 12 more white balls are added to the bag. Now if a ball drawn from the bag, the probability of drawing the white ball is 53y. Find the value of x.

36. At a fete, cards bearing numbers 1 to 1000, one number on one card, are put in a box. Each players select one card at random and that card is not replaced. If the selected card has a perfect square greater than 500, the player wins a prize. What is the probability that:

1. The first players win a prize?

2. The second player wins a prize, if the first has won?

37. Red queen and black jacks are removed from a pack of 52 playing cards. A card is drawn at random form the remaining cards, after remaining them. Find the probability that the drawn card is

1. A king

2. Of red colour

3. A face card 

4. A queen

38. Cards numbered 1 to 30 are put in a bag. A card is drawn at random from this bag. Find the probability that the number on the drawn card is.

1. Not divisible by 3.

2. A prime number grater than 7.

3. Not a perfect square number.

39.  A card is drawn at random from a well-shuffled deck of playing cards. Find the probability that the card drawn is 

1. A card of spade or an arc

2. A black king

3. Neither a jack nor a king

4. Either a king or a queen

40. A box contains cards bearing numbers from 6 to 70. If one card is drawn at  random from the box, find the probability that it bears.

1. A one digit number

2. A number divisible by 5

3. An odd number less than 30

4. A composite number between 50 and 70.