Q8 of 134 Page 32

The numbers 1, 2, 3 and 4 are written separately on four slips of paper. The slips are then put in a box and mixed thoroughly. A person draws two slips from the box, one after the other, without replacement. Describe the following events:

A = The number on the first slip is larger than the one on the second slip.


B = The number on the second slip is greater than 2


C = The sum of the numbers on the two slips is 6 or 7


D = The number on the second slips is twice that on the first slip.


Which pair (s) of events is (are) mutually exclusive?

Given: There are 4 slips in the box and mixed thoroughly.


To Find: Describe the given events .


Explanation: Here, Four slips of paper 1, 2, 3, and 4 are put in a box.


If Two slips are drawn from it one after the other without replacement. Then


The sample space for the experiment is:


S = {(1, 2)(1, 3), (1, 4)(2, 1)(2, 3)(2, 4)(3, 1)(3, 2)(3, 4)(4, 1)(4, 2)(4, 3)}


(i) A = number on the first slip is larger than the one on the second slip,


So, The sample space for A is:


{(2, 1)(3, 1)(3, 2)(4, 1)(4, 2)(4, 3)}


(ii) B = number on the second slip is greater than 2


So, The sample space for B is


{(1, 3)(2, 3)(1, 4)(2, 4)(3, 4)(4, 3)}


(iii) C = sum of the numbers on the two slips in 6 or 7


The sample space for C is


{(2, 4)(3, 4)(4, 2)(4, 3)}


(iv) D = number on the second slip is two times the number on the first slip


The sample space if:


{(1, 2)(2, 4)}


Now,


We can see, AՌD = Փ


Therefore, A and D are mutually exclusive events


Hence, A and D are mutually exclusive events.


More from this chapter

All 134 →
6

A die is thrown twice. Each time the number appearing on it is recorded. Describe the following events:

(i) A = Both numbers are odd.


(ii) B = Both numbers are even


(iii) C = sum of the numbers is less than 6.


Also, find A B, A B, A C, A C. Which pairs of events are mutually exclusive.

7

Two dice are thrown. The events A, B, C, D, E and F are describes as follows.

A = Getting an even number on the first die.


B. Getting an odd number on the first die.


C = Getting at most 5 as sum of the numbers on the two dice.


D = Getting the sum of the numbers on the dice greater than 5 but less than 10.


E = Getting at least 10 as the sum of the numbers on the dice.


F = Getting an odd number on one of the dice.


(i) Describe the following events: A and B, B or C, B and C, A and E, A or F, A and F


(ii) State true or false:


(a) A and B are mutually exclusive.


(b) A and B are mutually exclusive and exhaustive events


(c) A and C are mutually exclusive events


(d) C and D are mutually exclusive and exhaustive events


(e) C, d and E are mutually exclusive and exhaustive events


(f) A’ and B’ are mutually exclusive events


(g) A, B, F are mutually exclusive and exhaustive events

9

A card is picked up from a deck of 52 playing cards.

(i) What is the sample space of the experiment?


(ii) What is the event that the chosen card is a black faced card?

1

Find the component statements of the following compound statements:

(i) The sky is blue, and the grass is green.


(ii) The earth is round, or the sun is cold.


(iii) All rational numbers are real, and all real numbers are complex.


(iv) 25 is a multiple of 5 and 8.