NAT REVIEW 2023

  It is a variable being measured to produce numerical observations associated with the random outcomes of a chance experiment.

• fixed variable

• dependent variable

• independent variable       

• random variable

In a random experiment, what are possible outcome if a coin is tossed once?

• Tail (T) and Head (H)

• The number of dots 1,2,3,4,5,6

• Tail and Tail (TT), and Head and Head (HH)

• The pair of even number of dots (2,2),(2,4),(2,6),(4,2),(4,4),(4,6),(6,2),(6,4) and (6,6)

A fair coin is tossed three times and the sequence of

heads (H) and tails (T) is observed.

What is the probability that no heads will appear?

• 1/8

• 2/3

• 3/8

• 5/8

Which of the following is a discrete random variable?

• The number of patients in a hospital.

• The average weight of female athletes.

• The average amount of electricity consumed.

• The amount of paint used in repainting a building.

It is a list, a table, a graph, or a formula of probabilities associated with each of its possible values.

• Bar Chart

• Normal Distribution

• Probability Distribution Function

• Frequency Distribution Table

Does the following table represent a probability distribution?

• Yes, because each value of F(X) is between 0 and 1, and the sum of all values of F(X) is 1.

• No, because each value of F(X) is between 0 and 1.

• No, because the sum of all values of F(X) is 1.

• Yes, because all values of F(X) are the same.

Which probability value would satisfy the given probability distribution?

• 0.16

• 0.17

• 0.18

• 0.19

What is the mean of the probability distribution?

• 0.43`

• 1.66

• 1.26

• 1.64

What is the variance of the probability distribution?

• 1.66

• 1.08

• 1.01

• 2.20

Which of the following is NOT a property of a normal curve?

• The total area under it is 1.

• The curve is symmetric about the center.

• It is divided into positive 2 and negative 2 standard deviations

• The mean, median, and mode have the same value and are located at the same point.