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In: Statistics and Probability

Find the z-scores that cut off the middle 75% of a normal distribution.   a) ± 0.68...

Find the z-scores that cut off the middle 75% of a normal distribution.  

a) ± 0.68

b) ± 1.04

c) ± 1.15

d) ± 1.50

In a normal distribution with a mean = 10 and standard deviation = 2, what raw score corresponds to a z-score of 1.67?

a) 13.34

b) 6.66

c) 12.16

d) 8.28

With a -zscore of -2.0 and a raw score of 35, Lenny is asked by his professor to compute the standard deviation for a passing grade. The class average was 65. How should he respond?

a) 10

b) 5

c) 15

d) 2.5

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