ExamGOAL
Books
17
Subjective

Determine the probability $p$, for each of the following events.

(i) An odd number appears in a single toss of a fair die.

(ii) Atleast one head appears in two tosses of a fair coin.

(iii) A king, 9 of hearts or 3 of spades appears in drawing a single card from a well shuffled ordinary deck of 52 cards.

(iv) The sum of 6 appears in a single toss of a pair of fair dice.

Explanation

(i) When a die is throw the possible outcomes are

$$\begin{aligned} S & =\{1,2,3,4,5,6\} \text { out of which } 1,3,5 \text { are odd, } \\ \therefore \text { Required probability } & =\frac{3}{6}=\frac{1}{2} \end{aligned}$$

(ii) When a fair coin is tossed two times the sample space is

$$S=\{H H, H T, T H, T T\}$$

In at least one head favourable enonts are $H H, H T, T H$

$\therefore$ Required probability $=\frac{3}{4}$

(iii) Total cards $=52$

$$\begin{aligned} \text { Favourable } & =4 \text { king }+2 \text { of heart }+3 \text { of spade }=4+1+1=6 \\ \therefore \quad \text { Required probability } & =\frac{6}{52}=\frac{3}{26} \end{aligned}$$

(iv) When a pair of dice is rolled total sample parts are 36 . Out of which $(1,5),(5,1),(2,4)$, $(4,2)$ and $(3,3)$.

$\therefore$ Required probability $=\frac{5}{36}$

18
MCQ (Single Correct Answer)

In a non-leap year, the probability of having 53 Tuesday or 53 Wednesday is

A
$\frac{1}{7}$
B
$\frac{2}{7}$
C
$\frac{3}{7}$
D
None of these
19
MCQ (Single Correct Answer)

Three numbers are chosen from 1 to 20 . Find the probability that they are not consecutive

A
$\frac{186}{190}$
B
$\frac{187}{190}$
C
$\frac{188}{190}$
D
$\frac{18}{{ }^{20} C_3}$
20
MCQ (Single Correct Answer)

While shuffling a pack of 52 playing cards, 2 are accidentally dropped. Find the probability that the missing cards to be of different colours.

A
$\frac{29}{52}$
B
$\frac{1}{2}$
C
$\frac{26}{51}$
D
$\frac{27}{51}$
21
MCQ (Single Correct Answer)

If seven persons are to be seated in a row. Then, the probability that two particular persons sit next to each other is

A
$\frac{1}{3}$
B
$\frac{1}{6}$
C
$\frac{2}{7}$
D
$\frac{1}{2}$