Two hundred pre-engineering students have their midterm grades in the statistics, assuming normally distributed, a mean of 2.2 and a standard deviation of 0.6. How many of these students have their grades between 2.0 and 2.5 inclusive? A. 79 B. 84 C. 81 D. 78 E. 76
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To find the z-score for 2.0, we use the formula: z = (x - μ) / σ where x is the value, μ is the mean, and σ is the standard deviation. For 2.0: z = (2.0 - 2.2) / 0.6 z = -0.2 / 0.6 z = -0.3333 To find the z-score for 2.5: z = (2.5 - 2.2) / 0.6 z = 0.3 / 0.6 z = Show more…
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