1. A distribution has a mean of 60.0 and a standard deviation of 4.3. What perce
ID: 3156902 • Letter: 1
Question
1. A distribution has a mean of 60.0 and a standard deviation of 4.3. What percentage of scores fall between 62 and 65? 10.3% 69.62% 3% 19.62%
2. Which of the following is NOT true of the normal curve? It is a probability distribution. Its total area contains 100% of cases. It is skewed. The mean, median and mode are identical.
3. When calculating Sum of Squares, one should use the deviation method because it is quicker and easier. use the deviation method because it is more accurate. use the raw score method because it is more accurate. use the raw-score method because it is quicker and easier.
4.The probability of rolling a '6' on one toss of a standard six-sided die is: .167 .1 .25 .67 5. If two people are randomly selected (without replacement) from a class containing
5 psychology students and 15 nursing students, what is the probability of selecting 2 nursing students? 0.59 0.55 0.56 0.53
6. Scores that have a small standard deviation are not enough data to determine. relatively inconsistent. relatively consistent. invalid.
7. A distribution has a mean of 60.0 and a standard deviation of 4.3. What percentage of scores fall between 55 and 63? 34.2% 12% 63.5% 84.3%
8. When calculating the standard deviation for a sample, what should be in the denominator of the equation? N - 1 SS N s
9. A probability distribution is essentially a frequency distribution for no cases. an infinite number of cases. 100 cases. a small number of cases.
10. Empirical probabilities are: based on the normal curve. obtained only through carefully controlled laboratory conditions. never very high. essentially percentages based on a large number of observations.
11. Which of the following is a measure of variability? mean mode median standard deviation
12. Roughly ____ of the total area under the normal curve rests between the mean and one standard deviation above the mean. 25% 34% 50% 68%
Explanation / Answer
1. A distribution has a mean of 60.0 and a standard deviation of 4.3. What percentage of scores fall between 62 and 65?
We first get the z score for the two values. As z = (x - u) / s, then as
x1 = lower bound = 62
x2 = upper bound = 65
u = mean = 60
s = standard deviation = 4.3
Thus, the two z scores are
z1 = lower z score = (x1 - u)/s = 0.47
z2 = upper z score = (x2 - u) / s = 1.16
Using table/technology, the left tailed areas between these z scores is
P(z < z1) = 0.6808
P(z < z2) = 0.877
Thus, the area between them, by subtracting these areas, is
P(z1 < z < z2) = 0.1962 = 19.62% [ANSWER, D]
******************************
2. Which of the following is NOT true of the normal curve?
It is skewed. [ANSWER, C]
Note that the normal curve is symmetric, that's why.
*******************************************
Hi! Please submit the next part as a separate question. That way we can continue helping you! Please indicate which parts are not yet solved when you submit. Thanks!
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.