Question:
Let X be a random variable following binomial distribution whose mean and variance are 200 and 160, respectively. What is the value of the number of trials (n)?
Let X be a random variable following binomial distribution whose mean and variance are 200 and 160, respectively. What is the value of the number of trials (n)?
Options:
- a) 500
- b) 1000
- c) 1500
- d) 2000 Oswaal NDA/NA Year-wise Solved Papers
- a) 500
- b) 1000
- c) 1500
- d) 2000 Oswaal NDA/NA Year-wise Solved Papers
correct answer : b)
Explanation:
x = xp = 200 …(i)
s2 = xpq = 160 …
Þ q = 160
200
=
4
5
Þ p = 1 – 4
5
=
1
5
Þ n = 1000
x = xp = 200 …(i)
s2 = xpq = 160 …
Þ q = 160
200
=
4
5
Þ p = 1 – 4
5
=
1
5
Þ n = 1000