Q90.A fair coin is tossed n− times such that the probability of getting at least one head is at least 0. 9. Then the minimum value of n is _______. JEE Main 2021 (25 Jul Shift 2) JEE Main Previous Year Paper
What This Question Tests
This question assesses the understanding of basic probability, specifically calculating the probability of 'at least one head' using complementary probability for a series of independent coin tosses and solving an inequality.
Concepts Tested
Formulas Used
P(at least one head) = 1 - P(no heads)
P(event) = (1/2)^n for n tosses of a fair coin
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📋 Question Details
- Chapter
- Probability
- Topic
- Bernoulli trials & Probability of events
- Year
- 2021
- Shift
- 25 Jul Shift 2
- Q Number
- Q90
- Type
- Numerical
- NCERT Ref
- Class 12 Mathematics Ch 13: Probability
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