Chapter 5 - z-Scores: Location of Scores and Standardized Distributions - Problems - Page 147: 21

μ=78 When X = 70, σ=4, Z = $(70-78)/4$ = -2 σ=8, Z = $(70-78)/8 $= -1 σ=8 will give a better grade because its z-value is greater than the z-value when σ=4 b.When X = 80, σ=4, Z = $(80-78)/4$ = 0.5 σ=8, Z = $(80-78)/8$ = 0.25 σ=4 will give a better grade because its z-value is greater than the z-value when σ=8.

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