Download Mod 17 Normal Distribution ACT2

Module 17 Normal Distribution Activity 2
1. Bald eagles average about 12 pounds in weight with a standard deviation of 2 pounds. Suppose that
these weights follow the Normal model.
a. What is the probability that a randomly selected eagle is within 1 standard deviation of the mean
weight of 12 pounds?
b. What is the spread of weights for 1 SD?
c. What is the probability that a randomly selected eagle is within 2 standard deviation of the mean weight
of 12 pounds?
d. What is the spread of weights for 2 SD?
e. What is the probability that a randomly selected eagle is within 3 standard deviation of the mean
weight of 12 pounds?
f. What is the spread of weights for 3 SD?
2. Bald eagles mean wingspan is 6.7 feet with a standard deviation of 0.8 feet. Assume the wingspans
follow the Normal model.
a. Draw the normal distribution curve with the 68-95-99.7 cutoffs.
b. What is the typical wingspan of a bald eagle?
c. Approximately, what percent of all bald eagles have a typical wingspan?
d. An unusual wingspan for a bald eagle would be greater than _________feet and less than _______feet.
e. Approximately, what percent of all bald eagles would have an unusual wingspan?
f. An extremely unusual wingspan for a bald eagle would be greater than _________feet and less than
_______feet.
g. Approximately, what percent of all bald eagles would have an extremely unusual wingspan?
h. The largest bald eagles are found in Alaska. Some eagles in Alaska have been found to have a wingspan
of 8 feet. Convert this measurement to a z score and determine if this is considered unusual. Use 𝑧 =
i. The smallest bald eagles are found in South Carolina and have a wingspan of 6.2 feet. Convert this
measurement to a z score and determine if this is considered unusual. Use 𝑧 =
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.
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j. How does your normal curve with the 68-95-99.7 tick marks support your answers from part h and I
above?
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.
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