Probability And Statistics | Week 2

Course Name: Probability And Statistics

Course Link: Click Here

These are Probability And Statistics Week 2 Assignment 2 Answers


Q1. Two cards are drawn successively from a pack without replacing the first. If the first card is spade, then what is the probability that the second card is also a spade?
(A) 13/51
(B) 12/13
(C) 4/17
(D) 3/17

Answer: (C) 4/17


Q2. Four of the seven balls in a box have odd numbers on them. What is the probability that all three balls picked at random, one after the other, without replacement, have odd numbers?
(A) 24/343
(B) 4/35
(C) 2/7
(D) 64/343

Answer: (B) 4/35


These are Probability And Statistics Week 2 Assignment 2 Answers


Q3. Two urns contain respectively 2 white and 1 black balls, and 1 white and 5 black balls. One ball is transferred from the first to the second urn, and then a ball is drawn from the second urn. What is the probability that the ball drawn is white?
(A) 1/21
(B) 1/3
(C) 4/21
(D) 5/21

Answer: (D) 5/21


Q4. There are 2 boxes : Box-1 contains 3 silver spoons and 3 copper spoons and Box-2 contains 5 copper and 3 silver spoons. Assume that Box-1 is likely to be chosen with a probability of and Box-2 is likely to be chosen with a probability of A spoon is chosen at random from a box that has been randomly selected. What is the probability that it is a silver spoon?
(A) 11/24
(B) 1/3
(C) 1/8
(D) 5/24

Answer: (A) 11/24


These are Probability And Statistics Week 2 Assignment 2 Answers


Q5. The chance that a certain disease is diagnosed correctly is 60%. The chance that the patient will die under the treatment, after correct diagnosis is 40%; and the chance of death by wrong diagnosis is 70%. A patient who had the disease died. What is the probability that his/her disease was diagnosed correctly?
(A) 24/25
(B) 6/13
(C) 3/14
(D) 1/6

Answer: (B) 6/13


Q6. Let X be a discrete random variable with the p.m.f. as
X=x -2 -1 0 1 2
p(x) 1/9 2/9 3/9 2/9 1/9
Find P(|X|>1).

(A) 1/3
(B) 7/9
(C) 2/9
(D) 8/9

Answer: (C) 2/9


These are Probability And Statistics Week 2 Assignment 2 Answers


Q7. It is known that 2.5% of mobile phone chargers fail during the warranty period provided they are kept dry. The failure percentage is 5.6, if they are ever wet during the warranty period. If 91% of the chargers are kept dry and 9% are wet during warranty period, what is the probability that a phone charger fails during the warranty period?
(A) 0.3321
(B) 0.4392
(C) 0.0391
(D) 0.0278

Answer: (D) 0.0278


Q8. A random variables X has the following probability mass functions
X 0 1 2 3 4 5
P(X=x) 0 2k 3k 2k2 4k 9k2+k

Find P(X < 3).
(A) 0.622
(B) 0.378
(C) 0.455
(D) 0.471

Answer: (C) 0.455


These are Probability And Statistics Week 2 Assignment 2 Answers


Q9. Suppose the probabilities of n mutually independent events are P₁, P2,…, Pn respectively. Then what is the probability that at least one of the events will occur?
(A) 1- P₁ — Pn
(B) 1 (1-P₁) … (1-P)
(C) (1P₁) … (1-Pn)
(D) P₁ — Pn

Answer: (B) 1 (1-P₁) … (1-P)


Q10. Some elements in a chemical laboratory are highly contaminated. A high amount of contamination in an element is likely to exist with a 0.1 probability. The levels of contamination are evaluated on four randomly chosen elements. How likely is it that at least one of them has a high level of contamination?
(A) 0.2048
(B) 0.4096
(C) 0.6561
(D) 0.7408

Answer: (C) 0.6561


These are Probability And Statistics Week 2 Assignment 2 Answers

More Weeks of Probability and Statistics: Click Here

More Nptel courses: https://progiez.com/nptel


* The material and content uploaded on this website are for general information and reference purposes only. Please do it by your own first. COPYING MATERIALS IS STRICTLY PROHIBITED.


These are Probability And Statistics Week 2 Assignment 2 Answers


More from PROGIEZ

These are Probability And Statistics Week 2 Assignment 2 Answers