valid probability distribution quiz, statistics homework help

Probability is ____. (Points : 2)  the likelihood that some event will occur

  always expressed as a value between 0 and 1

  is the ratio of the number of favorable cases to the total number of possible cases

  all of the above

Question 2.2. The sum of the probability that an event will occur and the probability that it will not occur is ____. (Points : 2)  different for each case

  equal to P(E)

  equal to P(E)-1

  equal to 1

Question 3.3. The probability that an event will occur is written as follows (Points : 2)  P=1

  P(E)

  P(E-1)

  P(not E)

Question 4.4. Probability values are (Points : 2)  always more than 1.0

  always positive numbers

  only calculated for one-tailed tests

  always expressed as a fraction

Question 5.5. What proportion of a normal distribution is located in the tale beyond a Z score of +1.00? (Points : 2)  0.8413

  0.1587

  0.168

  0.3174

Question 6.6. A random sample requires that (Points : 2)  every individual has an equal chance of being selected

  individuals are selected from a convenience group

  no one knows how many people are in the population

  both a and b are correct

Question 7.7. For a population with a mean of 80 and a standard deviation of 10, what is the Z score corresponding to an individual score of 95? (Points : 2)  +0.25

  +0.50

  +0.75

  +1.50

Question 8.8. If the researcher’s alternative hypothesis stated, “females in this test will score higher than males” ____. (Points : 2)  this would be a two-tailed test

  it would be too early to make that statement

  this would be a null hypothesis

  this would be a one-tailed test

Question 9.9. If the null hypothesis stated that Group A results would be the same as Group B, would this represent a one-tailed or two-tailed test? (Points : 2)  One-tailed

  Two-tailed

  it could be either one depending on the groups

  cannot determine without additional information

Question 10.10. For a population with a mean of 80 and a standard deviation of 12, what is the Z score corresponding to an individual score of 92? (Points : 2)  +0.50

  +1.0

  +1.20

  +12.00