The following is a table of probabilties calculated from a survey of Bc students with the question asked "How many classes are you taking this semester?"

x: # of classes 1 2 3 4 5
P(x) 0.14 0.29 0.12 0.31 0.14

Using the table, find the following probabilities for a student selected at random:

a.) What is the probability that a student is taking 2 or more classes?
Incorrect

b.) What is the probability that a student is taking at least 3 classes?


c.) What is the probability that a student is taking more than 3 classes?


d.) What is the probability that a student is taking less than 2 classes?


e.) What is the probability that a student is taking no more than 2 classes?


f.) What is the average (mean) amount of classes a student takes at bC?


g.) What is the standard deviation for the amount of classes a student takes at BC? (round to two decimal places)

Respuesta :

Considering the discrete distribution, it is found that the desired measures are given as follows:

a) 0.86.

b) 0.57.

c) 0.45.

d) 0.14.

e) 0.43.

f) 3.02.

g) 1.31.

What is the probability distribution?


According to the table, it is given by:

P(X = 1) = 0.14.

P(X = 2) = 0.29.

P(X = 3) = 0.12.

P(X = 4) = 0.31.

P(X = 5) = 0.14.

Item a:

[tex]P(X \geq 2) = 1 - P(X < 2) = 1 - P(X = 1) = 1 - 0.14 = 0.86[/tex]

Item b:

[tex]P(X \geq 3) = 1 - P(X < 3) = 1 - P(X = 1) - P(X = 2) = 1 - 0.14 - 0.29 = 0.57[/tex]

Item c:

P(X > 3) = P(X = 4) + P(X = 5) = 0.31 + 0.14 = 0.45.

Item d:

P(X < 2) = P(X = 1) = 0.14.

Item e:

[tex]P(X \leq 2) = P(X = 1) + P(X = 2) = 0.14 + 0.29 = 0.43[/tex].

Item f:

The mean is given by the sum of each outcome multiplied by it's respective probability, hence:

E(X) = 0.14(1) + 0.29(2) + 0.12(3) + 0.31(4) + 0.14(5) = 3.02.

Item g:

The standard deviation is given by the square root of the sum of the difference squared of each observation and the mean, multiplied by it's respective probabilities, hence:

[tex]\sqrt{V(X)} = \sqrt{0.14(1-3.02)^2 + 0.29(2-3.02)^2 + 0.12(3-3.02)^2 + ... + 0.14(5-3.02)^2} = 1.31[/tex]

More can be learned about discrete probability distributions at https://brainly.com/question/24855677