Statistics and Probability Review 1

Which of the following is a discrete random variable?

• The average amount of electricity consumed

• The amount of painting used in repainting a building

• The number of patients in a hospital

• The aveage weight of female athletes

If two coins are tossed, which is not a possible value of the random variable for the number of heads?

• 0

• 1

• 2

• 3

If P(X)= x/6, what are the possible values of X for it to be a probability distribution?

• 0, 2, and 3

• 1, 2, and 3

• 2, 3, and 4

• 1, 1, and 2

Which of the following represents a probability distribution?

• 
• 
• 
• 

In a 30-item test, most of the students’ scores is closer to 21. In this situation, score of 21 is considered as the ____.

• Mean

• Median

• Standard Deviation

• Variance

The following are some of the properties of a normal distribution except

• Normal curve is a bell shaped.

• Its curve is symmetric to the x-axis.

• The total area under the curve is 1.

• The mean, median, and mode are equal.

The standard normal distribution has ________.

• Mean = 0, standard deviation = 0

• Mean = 1, standard deviation = 0

• Mean = 0, standard deviation = 1

• Mean = 1, standard deviation = 1

What percent will fall within the score 1000-1300?

• 86%

• 99%

• 95%

• 68%

What scores fall within 95% of the distribution?

• 1000 - 1300

• 700 – 1600

• 850 – 1450

• 1150 - 1600

What is the area under the normal curve above z=1.53? Hint: The area between 0 and 1.53 is 0.4370

• 0.0630

• 0.56300

• 0.9370

• 0.4370