NDA2010MathematicsProbabilityActual
The mean and variance of a binomial distribution are 8 and 4 respectively. What is P ( X =1) equal to?
Options
- A1 2¹²
- B1 2^8
- C1 2^6
- D1 2^4
Correct answer
A. 1 2¹²
Step-by-step solution
aligned & n p=8, n p q=4 & q= 1 2 , so p= 1 2 & n p=8, n 1 2 =8 n=16 aligned aligned & p( X =1)= ¹⁶ C ₁ ( 1 2 )¹⁵ ( 1 2 )^1 & =16 ( 1 2 )¹⁶= 1 2¹² aligned