15

Exam practic for Probability

Time: 35 Minutes                             Maximum Marks- 40

1.   In the adjoining figure, PA and PB are tangents from P to a circle with center. C If ∠APB = 40° then find ∠ACB.

(1 Mark)

1.   Cards bearing numbers 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 hearing:

        (i) a prime number less than 15.                        (ii) a number divisible by 3 and 5.

(4 Mark)

2.   Red kings, queens and jacks are removed from a deck of 52 playing cards and then well-shuffled. A card is drawn from these fining cards. Find the probability of getting (i) King (ii) a red card (iii) a spade.

(6 Mark)

3.   One card is drawn from a well-shuffled deck of 52 cards. Find the probability of getting:

        (i) A king of red suit.                        (ii) A queen of black suit.

        (iii) A jack hearts.                                (iv) A red face card.

(4 Mark)

4.   A bag contains 5 red balls and some blue balls. If the probability of drawing a blue ball from the bag is thrice that of a red ball, find the number of blue balls in the bag.

(3 Mark)

5.   In a throw of a coin, find the probability of getting a head.

(2 Mark)

6.   Two coins are tossed together find the probability of getting:

        (i) at least one tail.                        (ii) one head

(3 Mark)

7.   An unbiased die is thrown once, find the probability of getting:

        (i) a number greater than 4.                        (ii) a multiple of 3.

(3 Mark)

8.   Two dice are thrown at the same time. Find the probability of getting different numbers on both the dice.

(3 Mark)

9.   Two dice are thrown at the same time. Find the probability of getting same number on both the dice.

(3 Mark)

10.   A pair of dice is thrown once. Find the probability of getting an odd number on each the.

(2 Mark)

11.   A lot consists of 48 mobile phones of which 42 are good, 3 have only minor or defects and 3 have Or defects. Varnika will buy a phone if it is good but the trader will only buy a mobile if it has no major defect. One phone is selected at random from the lot. What is the probability that it is:

        (i) acceptable to. Varnika?                                (ii) acceptable to the trader?

(4 Mark)

12.   Find the probability that a number selected at random from the numbers 1, 2, 3, ..., 35 is a:

        (i) prime number                                (ii) multiple of 7

        (iii) a prime number less than 15.

(3 Mark)