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NCERT Class 12 Maths Chapter 13: Probability 14 Questions Solved

NCERT Solutions for Class 12 Maths Chapter 13 Probability — Exercise 13.3

Click any question below for its step-by-step NCERT textbook solution, concept hints, and worked explanation.

An urn has 5 red,5 black. Draw a ball, replace it and add two more of that colour, then draw again. Find P(second red).

Choose equally between bags I:4 red,4 black and II:2 red,6 black. A red ball is drawn. Find P(bag I|red).

60% of students are hostel residents,40% day scholars. A-grade rates are 30%,20% respectively. Given an A grade, find P(hostel).

A student knows an MCQ answer with probability 3/4; otherwise guesses and is correct with probability 1/4. Given a correct answer…

In the stated test model, disease prevalence is 0.1%, detection is 99%, and false-positive rate among healthy people is 0.5%. Find…

Choose equally among a two-headed coin, a 75%-heads coin and a fair coin. A head occurs. Find P(two-headed coin|head).

An insurer covers 2000 scooter,4000 car,6000 truck drivers, with accident rates 0.01,0.03,0.15. Given an accident, find P(scooter).

Machines A,B produce 60%,40% of output; defect rates are 2%,1%. Given a defective item, find P(B).

Groups I,II win with probabilities 0.6,0.4. New-product probabilities after winning are 0.7,0.3. Given a new product, find P(group II…

A girl rolls a fair die. On 5 or 6 she tosses a coin three times, otherwise once. Given exactly one head, find P(die was 1,2,3 or 4).

Operators A,B,C are used 50%,30%,20% of the time; their defect rates are 1%,5%,7%. Given a defective item, find P(A).

One uniformly random card is lost from 52. Two cards drawn from the remaining 51 are both diamonds. Find P(lost card is a diamond).

A speaks truth with probability 4/5. A fair coin is tossed and A reports head. Find P(actual head|report head).

If A⊂B and P(B)≠0, which conclusion is correct?