Q16.A coin is tossed three times. Let X denote the number of times a tail follows a head. If μ and σ2 denote the mean and variance of X , then the value of 64 (μ + σ2) is : (1) 51 (2) 64 (3) 32 (4) 48
What This Question Tests
The question involves defining a random variable for a sequence of coin tosses, determining its probability distribution, and then calculating its mean and variance.
Concepts Tested
Formulas Used
E(X) = Σx P(X=x)
Var(X) = E(X^2) - (E(X))^2
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📋 Question Details
- Chapter
- Probability
- Topic
- Random variables, Mean and Variance
- Year
- 2025
- Shift
- 22 Jan Shift 1
- Q Number
- Q16
- Type
- MCQ
- NCERT Ref
- Class 12 Mathematics Ch 13: Probability
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