Question

In: Statistics and Probability

The test scores for the analytical writing section of a particular standardized test can be approximated...

The test scores for the analytical writing section of a particular standardized test can be approximated by a normal​ distribution, as shown in the figure.

​(a) What is the maximum score that can be in the bottom

20%

of​ scores?

​(b) Between what two values does the middle

60%

of scores​ lie?

the mean is 3.3

the standard deviation is 0.77

* please show steps to solve for both for reference, thanks!

Solutions

Expert Solution

Refer Standard normal table/Z-table, Lookup for z-score corresponding to area 0.20 to the left of the normal curve or use excel formula "=NORM.S.INV(0.20)" to find the z-score.

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Refer Standard normal table/Z-table, Lookup for z-score corresponding to area 0.80 to the left of the normal curve or use excel formula "=NORM.S.INV(0.80)" to find the z-score.

orchestra answered 1 year ago
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