If Χ is a random variable that follows a normal distribution, state the following:
i. Two properties of the normal distribution
ii. A property that allows us to work out probabilities using
half of the distributi
If Z N ∼ (0,1) , find the following probabilities
(i) Ρ Ζ < − ( 1.78)
(ii) Ρ < Ζ < − (0.829 1.843)
(iii) Ρ Ζ < ( 2.326)
Solution :
i)
a) Normal distribution is symmetric distribution .
b) The mean , median and mode are equal .
ii)
P(Z < -1.78) = 0.0375
P(-0.829 < z < 1.843) = P(z < 1.843) - P(z < -0.829) = 0.7638
P(Z < 2.326 = 0.99
If Χ is a random variable that follows a normal distribution, state the following: i. Two...
2. Random variable Z has the standard normal distribution. Find the following probabilities a): P[Z > 2] b) : P[0.67 <z c): P[Z > -1.32] d): P(Z > 1.96] e): P[-1 <Z <2] : P[-2.4 < Z < -1.2] g): P[Z-0.5) 3. Random variable 2 has the standard normal distribution. Find the values from the following probabilities. a): P[Z > 2) - 0.431 b): P[:<] -0.121 c): P[Z > 2] = 0.978 d): P[2] > 2] -0.001 e): P[- <Z...
Which of the following is/are required for the probability distribution of a discrete random variable X with probabilities P(X= x), to be valid? I. PX x) is between 0 and 1 for all values of x. 2aPXx) ii. all x i, all x2 0 Il and Ill only Il only I and Il only I, II, and III only
distribution and finding probabilities using Z-distribution Find the following probabilities (i) P (Z < 1.54) = ? (ii) P (Z > 2.15) = ? (iii) P (Z < -1.37) = ?
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Let z denote a random variable having a normal
distribution with μ = 0 and σ = 1. Determine each of the following
probabilities. (Round your answers to four decimal places.)
(a)
P(z < 0.20) =
(b)
P(z < −0.20) =
(c)
P(0.30 < z < 0.86) =
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Do
the following in the program R
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