Answer to Question #60650 in Statistics and Probability for esita

Question

a) Let X be normally distributed and the mean of X is 12 and S.D. is 4. Find
i) ] P[X ≥ 20
ii) ] P[X ≤ 20
iii) ] p 0[ ≤ X ≤12
iv) x′ when 24.0 p[X > x′] =
v) 0
x′ and 1
x′, when 50.0 ( ) P x0
′ < X < x1
′ = and 25.0 ( ) P X > x1
′ = . (6)
b) A die is thrown 9000 times and the outcome of 3 or 4 is observed 3240 times. Show
that the die cannot be regarded as an unbiased one and find the limits between which
the probability of a throw of 3 or 4 lies