Question

A) A student learns that on his most recent exam in environmental science, the sample mean was 67.08 with a standard deviation of 16.81. He scored a 75. If we assume that this is a population, and is normally distributed, what proportion of students in the class scored worse than this student?

Enter your answer to four decimal places.

B) What proportion of the population scored better than the student in 6.43?

Enter your answer to four decimal places.

C) What proportion of the population scored between the mean and the student in 6.43?

Enter your answer to four decimal places.

Answer 1

A)

The following information has been provided:

We need to compute

. The corresponding z-value needed to be computed:

Therefore,

The following is obtained graphically:

B)

The following information has been provided:

We need to compute The corresponding z-value needed to be computed is:

Therefore, we get that

The following is obtained graphically:

C)

The following information has been provided:

We need to compute . The corresponding z-values needed to be computed are:

Therefore, we get:

The following is obtained graphically:

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