Answer:
(a) The value of f (0) is 0.3487.
(b) The value of f (2) is 0.1937.
(c) The value of P (X ≤ 2) is 0.9298.
(d) The value of P (X ≥ 1) is 0.6513.
(e) The value of E (X) is 1.
(f) The value of V (X) is 0.9 and <em>σ</em> is 0.9487.
Step-by-step explanation:
The random variable <em>X</em> follows a Binomial distribution with parameter <em>n</em> = 10 and <em>p</em> = 0.10.
The probability mass function of <em>X</em> is:
![P(X=x)={10\choose x}0.10^{x}(1-0.10)^{10-x};\ x=0,1,2,3...](https://tex.z-dn.net/?f=P%28X%3Dx%29%3D%7B10%5Cchoose%20x%7D0.10%5E%7Bx%7D%281-0.10%29%5E%7B10-x%7D%3B%5C%20x%3D0%2C1%2C2%2C3...)
(a)
Compute the value of <em>f</em> (0) as follows:
f (0) = P (X = 0)
![={10\choose 0}0.10^{0}(1-0.10)^{10-0}\\=1\times 1\times 0.348678\\=0.348678\\\approx0.3487](https://tex.z-dn.net/?f=%3D%7B10%5Cchoose%200%7D0.10%5E%7B0%7D%281-0.10%29%5E%7B10-0%7D%5C%5C%3D1%5Ctimes%201%5Ctimes%200.348678%5C%5C%3D0.348678%5C%5C%5Capprox0.3487)
Thus, the value of f (0) is 0.3487.
(b)
Compute the value of <em>f</em> (2) as follows:
f (2) = P (X = 2)
![={10\choose 2}0.10^{2}(1-0.10)^{10-2}\\=45\times 0.01\times 0.43047\\=0.1937115\\\approx0.1937](https://tex.z-dn.net/?f=%3D%7B10%5Cchoose%202%7D0.10%5E%7B2%7D%281-0.10%29%5E%7B10-2%7D%5C%5C%3D45%5Ctimes%200.01%5Ctimes%200.43047%5C%5C%3D0.1937115%5C%5C%5Capprox0.1937)
Thus, the value of f (2) is 0.1937.
(c)
Compute the value of P (X ≤ 2) as follows:
P (X ≤ 2) = P (X = 0) + P (X = 1) + P (X = 2)
![=\sum\limits^{0}_{2} {{10\choose x}0.10^{x}(1-0.10)^{10-x}}\\=0.3487+0.3874+0.1937\\=0.9298](https://tex.z-dn.net/?f=%3D%5Csum%5Climits%5E%7B0%7D_%7B2%7D%20%7B%7B10%5Cchoose%20x%7D0.10%5E%7Bx%7D%281-0.10%29%5E%7B10-x%7D%7D%5C%5C%3D0.3487%2B0.3874%2B0.1937%5C%5C%3D0.9298)
Thus, the value of P (X ≤ 2) is 0.9298.
(d)
Compute the value of P (X ≥ 1) as follows:
P (X ≥ 1) = 1 - P (X < 1)
= 1 - P (X = 0)
= 1 - 0.3487
= 0.6513
Thus, the value of P (X ≥ 1) is 0.6513.
(e)
Compute the expected value of <em>X</em> as follows:
![E(X)=n\times p](https://tex.z-dn.net/?f=E%28X%29%3Dn%5Ctimes%20p)
![=10\times 0.10\\=1](https://tex.z-dn.net/?f=%3D10%5Ctimes%200.10%5C%5C%3D1)
Thus, the value of E (X) is 1.
(f)
Compute the variance of <em>X</em> as follows:
![V(X)=np(1-p)](https://tex.z-dn.net/?f=V%28X%29%3Dnp%281-p%29)
![=10\times 0.10\times (1-0.10)\\=0.90](https://tex.z-dn.net/?f=%3D10%5Ctimes%200.10%5Ctimes%20%281-0.10%29%5C%5C%3D0.90)
Compute the standard deviation of <em>X</em> as follows:
![SD(X)=\sqrt{V(X)}](https://tex.z-dn.net/?f=SD%28X%29%3D%5Csqrt%7BV%28X%29%7D)
![=\sqrt{0.90}\\=0.94868\\\approx0.9487](https://tex.z-dn.net/?f=%3D%5Csqrt%7B0.90%7D%5C%5C%3D0.94868%5C%5C%5Capprox0.9487)
Thus, the value of V (X) is 0.9 and <em>σ</em> is 0.9487.