Answer:
83.8
Explanation:
use the z-score formula:
z = (X - μ) / σ
where X is the test statistic (the grade we're trying to find in this case), μ is the mean, σ is the standard deviation.
z = (X - μ) / σ
1.6 = (X - 71) / 8
8(1.6) = X - 71
12.8 = X - 71
X = 12.8 + 71
= 83.8.
z-score of 1.6 (A grade) is grade of 83.8