FiltersDone

Question type

Essay

Multiple Choice

Short Answer

True False

Matching

Exam 6: Probability

Show Answer

Share

---

All types

Filters

Study FlashcardsPractice ExamLearn

Question 31

Multiple Choice

Review LaterAdd Note

Review Later

A normal distribution has a mean of µ = 80 with σ = 20.What score separates the highest 15% of the distribution from the rest of the scores?

A) X = 59.2
B) X = 100.8
C) X = 95
D) X = 65

E) B) and D)
F) A) and D)

Correct Answer

verified

Show Answer

Question 32

Multiple Choice

Review LaterAdd Note

Review Later

IQ scores form a normal distribution with µ = 100 and σ = 15.Individuals with IQs above 140 are classified in the genius category.What proportion of the population consists of geniuses?

A) 0.9962
B) 0.5038
C) 0.4962
D) 0.0038

E) A) and B)
F) All of the above

Correct Answer

verified

Show Answer

Question 33

True/False

Review LaterAdd Note

For any normal distribution,the probability of randomly selecting a z-score less than z = 1.40 is p = 0.9192.

What z-score value separates the highest 70% of the scores in a normal distribution from the lowest 30%?

A vertical line drawn through a normal distribution at z = 1.40 divides the distribution into two sections.The proportion in the smaller section is 0.0808.

A vertical line drawn through a normal distribution at z = 0.50 separates the distribution into two sections,the body and the tail.What proportion of the distribution is in the body?

The middle 95% of a normal distribution is located between z = 1.96 and z = -1.96

What proportion of a normal distribution is located between the mean and z = 1.40?

For a normal distribution,the z-score boundary that separates the highest 2.5% of the scores from the rest is z = -1.96.

All probabilities can be expressed as decimal values ranging from 0 to 1.00.

The proportion in the body of a normal distribution can never be less than 0.50.

A normal distribution has a mean of µ = 40 with σ = 10.If a vertical line is drawn through the distribution at X = 55,what proportion of the scores are on the right side of the line?

For a population with a mean of μ = 80 and σ = 10,only 2.28% of the scores are greater than X = 100.

The proportion in the tail of a normal distribution can never be more than 0.50.

A class consists of 10 males and 30 females.If one student is randomly selected from the class,what is the probability of selecting a male?

A normal distribution has a mean of µ = 100 with σ = 20.If one score is randomly selected from this distribution,what is the probability that the score will have a value between X = 80 and X = 100?

A normal distribution has a mean of µ = 70 with σ = 12.If one score is randomly selected from this distribution,what is the probability that the score will be greater than X = 55?

A vertical line is drawn through a normal distribution so that the proportion in the tail is 0.1841.The line was drawn at z = 0.90 or at z = -0.90.

A vertical line drawn through a normal distribution at z = -0.75 separates the distribution into two sections.The proportion in the smaller section is 0.2734.

Which of the following accurately describes the proportions in the tails of a normal distribution?