Suppose the test scores of students in a class are normally distributed with a mean of 85 and a standard deviation of 4. What is
1 answer:
Answer:
B
Step-by-step explanation:
Converting it to z, we can use the formula of z-score:
z-score =
Where
x is the value we are checking for (here, x = 79)
is the mean, which is 85
is the standard deviation, which is 4 now
<em>Let's plug the information into the formula and solve for the answer:</em>
<em></em>
<em />
<em>B is the correct answer.</em>
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a. Square cross sections will contribute a volume of
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