SOLUTION: 11. In 2000, as reported by the ACT Research Service, the mean ACT Math score was 20.7. If ACT math scores are normally distributed with o = 5, answer the following questions. Rou

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Question 1192028: 11. In 2000, as reported by the ACT Research Service, the mean ACT Math score was 20.7. If ACT
math scores are normally distributed with o = 5, answer the following questions. Round to 2
decimal places.
=
a. If a student's ACT Math score is better than 80% of the students taking the exam (80'
percentile), what was his score? Hint: If you score better than someone, would their score be higher
or lower than yours? This will indicate which way you should shade!
b. A certain college considers only applications in which the ACT Math score is in the top 5% of
scores. What score is required to be considered?
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
80% percentile is z=0.8416
so z=(x-mean)/sd
0.8416=(x-20.7)/5
4.208=x-20.7
x=25.91
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top 5% is z=1.645
this becomes 8.225=(x-20.7)
x=28.93