Q90.Minimum number of times a fair coin must be tossed so that the probability of getting at least one head is more than 99% is: (1) 8 (2) 6 (3) 5 (4) 7 JEE Main 2019 (10 Apr Shift 2) JEE Main Previous Year Paper
What This Question Tests
This question tests the concept of complementary probability for 'at least one head' in a series of coin tosses and solving an inequality for the minimum number of trials.
Concepts Tested
Formulas Used
P(at least one head) = 1 - P(no heads)
P(getting tail in one toss) = 1/2
📚 NCERT Sections This Tests
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📋 Question Details
- Chapter
- Probability
- Topic
- Probability of events in Bernoulli trials
- Year
- 2019
- Shift
- 10 Apr Shift 2
- Q Number
- Q90
- Type
- MCQ
- NCERT Ref
- Class 12 Mathematics Ch 13: Probability
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