Jay9187viz
Answered

the scores of students who took a 100-item exam resemble a normal distribution with a mean of 85 and a standard deviation of 5. the teacher would like to get the lowest 10 percent of the scores and invite those students for a remedial class. what range of scores indicates inclusion in the remedial class
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Sagot :

Answer:

Using the normal distribution table, the z-score closest to the lowest 10% is [tex]z=-1.28[/tex]

Find the score corresponding to this z-score.

x = zσ + μ

x = -1.28(5) + 85 = 78.6

So, the range of scores is between 0 to 79 (or 78)

Note: I think this requires an integer answer. If you round the number, you'll get 79 (around lowest 12%). However, if you strictly follow the lowest 10%, then it's 78 (around lowest 8%).