Q90.The minimum number of times one has to toss a fair coin so that the probability of observing at least one head is at least 90% is: (1) 2 (2) 4 (3) 5 (4) 3 JEE Main 2019 (08 Apr Shift 2) JEE Main Previous Year Paper
What This Question Tests
This question requires calculating the minimum number of coin tosses needed to achieve a specified probability of observing at least one head, using the concept of complementary probability.
Concepts Tested
Formulas Used
P(at least one head) = 1 - P(no heads)
P(no heads in n tosses) = (1/2)^n
📚 NCERT Sections This Tests
3.18 — For A First Order Reaction, Show That Time Required For 99% Completion
Chemistry Class 11 · Chapter 3
3.18 For a first order reaction, show that time required for 99% completion is twice the time required for the completion of 90% of reaction.
12.5 — A Hydrogen Atom Initially In The Ground Level Absorbs A Photon,
Physics Class 12 · Chapter 12
12.5 A hydrogen atom initially in the ground level absorbs a photon, which excites it to the n = 4 level. Determine the wavelength and frequency of photon.
9.19 — A Screen Is Placed 90Cm From An Object. The Image Of The Object On
Physics Class 12 · Chapter 9
9.19 A screen is placed 90cm from an object. The image of the object on the screen is formed by a convex lens at two different locations separated by 20cm. Determine the focal length of the lens.
📋 Question Details
- Chapter
- Probability
- Topic
- Bernoulli Trials and Binomial Distribution
- Year
- 2019
- Shift
- 08 Apr Shift 2
- Q Number
- Q90
- Type
- MCQ
- NCERT Ref
- Class 12 Mathematics Ch 13: Probability
More from this Chapter
Q90.One ticket is selected at random from 50 tickets numbered 00, 01, 02, … , 49. Then the probability that the sum of the digits on the selected ticket is 8 , given that the product of these digits is zero, equals (1) 1 (2) 1 14 7 (3) 5 (4) 1 14 50 JEE Main 2009 JEE Main Previous Year Paper
Q89.Four numbers are chosen at random (without replacement) from the set {1, 2, 3, … . , 20} . Statement-1: The probability that the chosen numbers when arranged in some order will form an AP is 1 . Statement-2: If the 85 four chosen numbers from an AP, then the set of all possible values of common difference is {±1, ±2, ±3, ±4, ±5}. (1) Statement-1 is true, Statement-2 is true; (2) Statement-1 is true, Statement-2 is false Statement-2 is not the correct explanation for Statement-1 (3) Statement-1 is false, Statement-2 is true (4) Statement-1 is true, Statement-2 is true; Statement-2 is the correct explanation for Statement-1
Q90.An urn contains nine balls of which three are red, four are blue and two are green. Three balls are drawn at random without replacement from the urn. The probability that the three balls have different colour is (1) 2 (2) 1 7 21 (3) 2 (4) 1 23 3 JEE Main 2010 JEE Main Previous Year Paper
Q89.Consider 5 independent Bernoulli's trials each with probability of success p . If the probability of at least one failure is greater than or equal to 31 , then p lies in the interval 32 (1) ( 34 , 1112 ] (2) [0, 12 ] (3) ( 1112 , 1] (4) ( 12 , 34 ]