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the scores on a standardized test are normally distributed with a mean of 500 and a standard deviation of 100. sofia scored 632 on the test. what percent of students scored below sofia?

User Dagmara
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2 Answers

4 votes
90.66% of students scored below sofia
User Thunderblaster
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Answer: About 90.66% of students scored below Sofia.

Explanation:

Given : The scores on a standardized test are normally distributed with
\mu=500 and
\sigma=100

Using the formula for z-value :


z=(x-\mu)/(\sigma)

Z-score for x= 632 will be :-


z=(632-500)/(100)=1.32

Using standard normal distribution table for z, the probbaillity that the students scored below Sofia will be :-


P(z<1.32)=0.9065825\approx0.9066

In percent,
0.9066*100=90.66\%

Hence, about 90.66% of students scored below Sofia.

User Werrf
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8.5k points