Probability

Probability

1. The probability of drawing a red card from a deck of playing cards is

1. Total number of cards n(S) = 52
Number of red cards n(E) = 26
∴ P(E) = n(E)/n(S)

Correct Option: D

Total number of cards n(S) = 52
Number of red cards n(E) = 26
∴ P(E) = n(E)/n(S) = 26/52 = 1/2

1. Find the probability that a vowel selected at random from the 5 vowels is an 'i'. ?

1. Here, n(5) = {a, e, i,o, u}
and E = Event of selecting the vowel i = {i}

Correct Option: C

Here, n(5) = {a, e, i,o, u}
and E = Event of selecting the vowel i = {i}
∴ P(E)= n(E)/n(S) = 1/5

1. If the probability that A will live 15 yr is 7/8 and that B will live 15 yr is 9/10, then what is the probability that both will live after 15 yr ?

1. Required probability = P(A) x P(B)

Correct Option: B

Required probability = P(A) x P(B)
= (7/8) x (9/10)
= 63/80

1. A single letter is selected at random from the word 'PROBABILITY' . The probability that it is a vowel, is ?

1. Total number of letters = n(S) = 11
whereas, number of vowels = n(E) = 4
∴ Required probability = n(E)/n(s)

Correct Option: B

Total number of letters = n(S) = 11
whereas, number of vowels = n(E) = 4
∴ Required probability = n(E)/n(s) = 4/11

1. A card is drawn from a well shuffled pack of cards. The probability of getting a queen of club or king of heart is ?

1. Total ways = 52
There is one queen of club and one king of heart favourable ways = 1 + 1 = 2.

Correct Option: B

Total ways = 52
There is one queen of club and one king of heart favourable ways = 1 + 1 = 2.
∴ Required probability = 2/52 = 1/26