Addition Theorem on Probability - Basic Level

Addition Theorem on Probability - Basic Level

Dear Readers,

Probability means possibility. It is a branch of mathematics that deals with the occurrence of a random event. The value is expressed from zero to one. Probability has been introduced in Maths to predict how likely events are to happen. The meaning of probability is basically the extent to which something is likely to happen. This is the basic probability theory, which is also used in the probability distribution, where you will learn the possibility of outcomes for a random experiment. To find the probability of a single event to occur, first, we should know the total number of possible outcomes. .

Q1. A bag contains 5 brown and 4 white socks. A man pulls out two socks. The probability that these are of the same colour is

•  5/108
•  18/108
•  30/108
•  48/108

Solution
The probability that these are of the same colour is 48/108

Q2.The probability that a leap year will have 53 Fridays or 53 Saturdays is

•  2/7
•  3/7
•  4/7
•  1/7

Solution
The probability that a leap year will have 53 Fridays or 53 Saturdays is 3/7

Q3.  A box contains 10 good articles and 6 with defects. One article is chosen at random. What is the probability that it is either good or has a defect

•  24/64
•  40/64
•  49/64
•  64/64

Solution
probability that it is either good or has a defect is 64/64

Q4. The probabilities of occurrence of two events are respectively 0.21 and 0.49. The probability that both occurs simultaneously is 0.16. Then the probability that none of the two occurs is

•  0.30
•  0.46
•  0.14
•   None of these

Solution
probability that none of the two occurs is 0.46

Q5.A bag contains 30 balls numbered from 1 to 30, one ball is drawn randomly. The probability that number on the ball is multiple of 5 or 7 is

•  1/2
•  1/3
•  2/3
•  1/4

Solution
 probability that number on the ball is multiple of 5 or 7 is 1/3

Q6. If the probability of X to fail in the examination is 0.3 and that for Y is 0.2, then the probability that either X or Y fail in the examination is

•  0.5
•  0.44
• 0.6
•  None of these

Solution
probability that either X or Y fail in the examination is 0.44

Q7.A card is drawn from a well shuffled pack of cards. The probability of getting a queen of club or king of heart is

•  1/52
•  1/26
•  1/18
•  None of these

Solution
The probability of getting a queen of club or king of heart is 1/26

Q8.A bag contains 5 black balls, 4 white balls and 3 red balls. If a ball is selected randomwise, the probability that it is a black or red ball is

•  1/3
•  1/4
•  5/12
•  2/3

Solution
probability that it is a black or red ball is 2/3

Q9.A card is drawn from a pack of cards. Find the probability that the card will be a queen or a heart

•  4/3
•  16/3
•  4/13
•  5/3

Solution
probability that the card will be a queen or a heart is 4/13

Q10. The chance of India winning toss is 3/4. If it wins the toss, then its chance of victory is 4/5 otherwise it is only 1/2. Then chance of India's victory is

•  1/5
•  3/5
•  3/40
•  29/40

Solution
chance of India's victory is 29/40