Facts
Z-Scores
Percentiles Z
X-Values
Percentiles X
100
In a Normal Model, 50% of the data falls below this.
What is the mean?
100
The area below z = 1.15
What is .8749?
100
25% of the data in a normal model are below this z-score.
What is z = -0.67?
100
A normal model has a mean = 230 and a standard deviation = 15. Find the following: P(x < 210)
What is .0918?
100
A normal distribution has a mean = 17.1 and a standard deviation = 4. This x value represents cutoff for the bottom 10%.
What is 11.98?
200
The shape of the Normal Model is this.
What is a bell-curve. OR Symmetric and Unimodal.
200
The area above z=0.32
What is .3745?
200
72% of data in a normal model fall below this z-score.
What is z=0.58?
200
A normal model has a mean = 135 and a standard deviation = 10.4. Find the following : P(x > 146)
What is 0.1446?
200
A normal model has a mean = 11.4 and a standard deviation = 3. This x value represents the values above the top 10%.
What is 15.24?
300
These percentages roughly represent the percent of the data values that fall within one, two, and three standard deviations from the mean of a normal distribution.
What is 68% - 95% - 99.7%?
300
The area above z = -2.81
What is .9975?
300
93% of data in a normal model fall above this z-score.
What is z=-1.48?
300
A normal model has a mean = 86 and a standard deviation = 5. Find the following: P(85 < x < 95)
What is 0.5434?
300
The mean math SAT score is 511 with a standard deviation of 120, and follows a normal model. This SAT score separates the top 2% from the rest of the data.
What is 757?
400
The total area under the curve of a normal distribution is this.
What is 1?
400
The area between z = -1.00 and z = 0.50.
What is .5328?
400
The middle 70% of data in a normal model fall between which z-scores?
What are z = -1.04 and z = 1.04?
400
The mean number of Coney Island hot dogs that Mike can eat in one sitting is 5.8 with a standard deviation of 1.1, and follows a normal model. This is the probability he eats more than 8 hot dogs.
What is .0228?
400
The mean math SAT score is 511 with a standard deviation of 120 and follows a normal model. 90% of students should fall between these scores. (Round to the nearest whole number).
What are 314 and 708?
500
The mean of a z-score distribution is always equal to ____, and the standard deviation is always equal to ____.
What is 0 and 1?
500
The area that coincides with |z| > 1.25.
What is .2113?
500
In a normal model, this z-score is also Q3.
What is z = 0.67?
500
In 2015, the mean math SAT score was a 511 with a SD of 120, and follows a normal model. This is the probability of scoring between a 720 and a 780.
What is .0283?
500
Again, the mean math SAT score is 511 with a standard deviation of 120, and follows a normal model. These values represent Q1, Median, and Q3. (Round to the nearest whole value).
What are 430, 511, and 592?