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Free-response questions on the AP Statistics Exam are graded 4, 3, 2, 1, or~ 0. Question 2 on the exam was of moderate difficulty. The average score on question 2 was 2.05 with a standard deviation of 1. To the nearest tenth, what score was achieved by a student who was at the 90th percentile of all students on the test? You may assume that the scores on the question were approximately normally distributed. 
Overseas Competition->Knowledge Point->Calculation Modules->Fractions
\textbf{Z = 1.28}  \textbf{$$\frac{x-2.05}{1}$$ = 1.28}  \textbf{x= 3.33} 