SD and Normal Distribution Worksheet

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Multiple Choice Warm-up to go with SD and Normal Distribution
Worksheet
1)
2)
3)
4)
There is no 5 and 6.
#1) 28 31 34 35 37 41 42 42 42 47
49 51 52 52 60 61 67 72 75 77
#3) Age:
18 19 20 21 22 23
24 25 32
Number of students:14 120 200 200
90
30
10
2
1
Quiz on 2.4 and 2.5 Next class!
• Make sure you understand cummulative
percentile graphs
• Understand normal distribution problems:
know how to draw the curve with labels.
• Know how to solve the for the percentile or
proportion of data between or below a
number in distribution curve.
2.5 H.W. #63 - 65
63) i. 0.6318 or 63.18% ii. 0.0394 or 3.94% iii. 0.3101 or 31%
64) Mean is 511 and the standard deviation is 112
The college is looking for the top 20% or 80th percentile or
above. You could use invNorm(0.8, 511, 112) = 605 OR estimated
using the 68, 95, 99.7 rule.
From 0 to the mean of 511 is 50% of the scores, plus 1 SD
would make it 84% (near the 80th percentile) 511+ 112= 623
65) For males normalcdf (62, 72, 70.1, 2.5) = 0.7758 or 77.6%
For females normalcdf(62,72,64.8,2.5) = 0.8667 or 86.7%
Student of the day!
Block 4
Student of the day!
Block 5
Student of the day!
Block 6
Chebychev’s Rule Re-visited
#6 of Multiple Choice Yesterday
A set of 5,000 scores on a college readiness exam with a
mean of 72 and an s.d. of 6. If the scores are not normally
distributed, what can be said of the scores less than 58.
First: Use z-score to find how many s.d. 58 is from the
58  72  14
mean.

  2.33
6
6
Using Chebyshev’s rule for what is NOT within 2.33 s.d.
1
from the mean:
 18 .37 %
2
2.33
This is above 2.33 and below 2.33; 18.37% of 5,000 is 918
students ….that is the closest to the correct answer that can
be chosen since the curve is not normally distributed.
#10 of Multiple Choice use InvNorm
The mean was 2.05 with an s.d. of 1, to the nearest
tenth what was a score of someone in the 90th
percentile.
InvNorm reverses normalcdf
InvNorm (when mean and s.d. are entered) give
the proportion below that value.
InvNorm(.9, 2.05, 1) = 3.33 or choice B
Review Answers
a
e
Answers to Multiple Choice continued…
d
b
d
Answer to multiple choice
b
e
a
d
b
Using the z-score table.
SD and Normal Distribution Worksheet
Problem #1
SD and normal distribution worksheet
Problem #3
Draw and label the bell curve for both cows.
SD and normal distribution worksheet
Problem #4
H.W. Assignment
• Normal Distribution Worksheet #1 and #2
• Be prepared for quiz on 2.4 and 2.5 next class!
• Have your notes and warm-ups organized in the notes
section of your notebook. You should all 10 terms copied
and defined for 2.4 and 2.5 in your definition section in
your notebook.
10 pts for terms (1pt each) from recentering to standard
unit z-score; 15 pts for each of the notes(10pts) with
warm-up (5pts) 6x 15pts = 90 pts for Notes
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