Finding Z Score
Using Z Score
Data Analysis
Miscellaneous
Bias/Sampling
100
Find the z score if x = 60, mean = 65, and standard deviation = 2.5
-2
100
What percent of the data is below a z-score of 0.63?
73.6%
100
Is the following data set likely to be left skewing or right skewing?
Right Skewed
100
Which of the following is the symbol for Population standard deviation A. μ B.
A. μ \quad B.\barx \quad C. σ \quad D. Sx
C. σ
100
Amy, a reporter, wants to survey workers about where they eat lunch during a typical work week. She writes a column asking workers to call a special phone number and identify where they eat lunch during a typical work week. What type of bias can come from this type of sampling method?
What is self-selected/nonresponse. The workers can choose whether or not to respond.
200
Find the mean when z = 3, x = 70, and standard deviation = 4
58
200
What is the area under the standard curve corresponding to Z < 1.31?
.90490
200
The range and sample standard deviation of this data set 47, 18, 65, 28, 43, 18
What is... Range - 47, Sx - 18.6 ?
200
The probability of selecting a data point from your set to be under the normal curve is always ____ .
100%
200
Baltimore city sent out a survey to a sample of residents asking what their greatest neighborhood needs are. The survey was sent to all of the apartments in the Inner Harbor area. What type of bias is this most likely to result in?
Undercoverage
300
Find x when z = 1.5, standard deviation = 3, and mean = 50
54.5
300
What is the area under the standard curve corresponding to Z > 0.05?
.51994
300
The mean, median, and mode of this data set. 6, 22, 4, 15, 10, 8, 8, 7, 14, 20
What is... Mean - 11.4 Median - 9 Mode - 8 ?
300
The median number of pets owned is:
1
300
Mr. Dingle wanted to know if the students in his class wanted to play jeopardy. He asked the first 5 students to arrive in each of his classes one day. What type of Sample is this most likely to be?
Convenience
400
Find standard deviation when z = 2.5, x = 60, and mean = 55
2
400
What is the area under the standard curve corresponding to -.0.4 < Z < 1.9?
.6267
400
The range and population standard deviation of this data set. 29.4, 22.9, 15.7, 26.9, 24.0, 27.5, 11.4
What is... Range - 18, σ - 6.1 ?
400
The Z score of the mean is always ____.
Zero
400
A Nike representative wanted to check for defects in Nike sneakers sold in Baltimore area stores. She assumed the Nikes would be randomly distributed to different stores. She chose a 3 different stores and checked all of the Nikes in those stores. This is an example of what type of sampling?
Cluster random sampling
500
If the z score = -4.5, x = 15, and mean is three times x, what is the standard deviation?
6.66
500
Scores on the ACT test for the 2004 high school graduating class had a mean of 20.9 and a standard deviation of 4.8. In all, 1,171,460 students in this class took the test, and 1,052,490 of them had scores of 27 or lower if the distribution of scores were normal, what percent of scores would be 27 or lower? What percent of actual scores were 27 or lower? Does the normal distribution describe the actual data well?
Table Percentage: 90% Actual Percentage: 90% Yes
500
The mean, median of this data. 0.12, 0.54, 0.36, 0.17, 0.36, 0.94, 0.88
IS IT SYMMETRICAL, LEFT SKEWING, OR RIGHT SKEWING
What is.... Mean - about 0.48 Median - 0.36
SKEW: RIGHT
500
It is a mathematical table that allows us to know the percentage of values below (to the left) a z-score in a standard normal distribution (SND).
Z score table
500
Mrs. Claus wanted to find out what activities seniors were most interested in doing on their NYC trip. Rather than ask all seniors she assigned a number to each student and used a random number generator to select students for her sample. This is an example of what type of random sample?
SRS (Simple Random Sample)