Download Normal Distribution using the curve, worksheet

Normal distribution
This curve is based on a distribution with a mean of 0 and a standard deviation of 1.
Question 1
What proportion of this distribution is:
a. Greater than 0
b. Greater than 1
c. Less than 1
d. Between -1 and 1 ?
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Question 2
120
This new curve is a distribution with a mean of 120 and a standard deviation of 1.
Using the percentages from the original curve, what proportion of this distribution is:
e. Greater than 120
f. Greater than 121
g. Less than 122
h. Between 119.5 and 121 ?
Question 3
140
This new curve is a distribution with a mean of 140 and a standard deviation of 2.
Using the original curve, what proportion of this distribution is:
i.
Greater than 140
j.
Greater than 143
k. Less than 144
l.
Between 139 and 141 ?
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Question 4
164
This new curve is a distribution with a mean of 164 and a standard deviation of 5.
Using the original curve, what proportion of this distribution is:
m. Greater than 171.5
n. Less than 176.5
o. Less than 154
p. Between 159 and 161 ?
Question 5
Data was collected from a small sample of houseflies.
This graph was used to determine the nature of the distribution.
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a. Describe two properties of the graph which indicate that the distribution might be a
normal distribution.
b. Estimate the mean and standard deviation for this distribution. Explain your
answers.
Further investigation revealed that the population mean wing length is 4.55mm and the
standard deviation 0.39
Find what proportion of houseflies have a wing length of:
c. Less than 4.94mm
d. More than 4.16mm
e. Between 4.16mm and 4.94mm
f. Less than 5.33mm.
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