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After collecting the data, Peter finds that the standardized test scores of the students in a school are normally distributed with mean 85 points and standard deviation 3 points. Use the Empirical Rule to find the probability that a randomly selected student's score is greater than 76 points. Provide the final answer as a percent rounded to two decimal places.

2 Answers

5 votes

Answer:

mean=85

sd=3

85-3*3=76

its between 76 and 85=99.7/2=49.85%

50% mean above.

49.85+50=99.85%

Explanation:

User Carleto
by
3.7k points
3 votes

Answer:

Explanation:

Given that:

the standardized test scores of the students in a school are normally distributed with:

mean = 85 points

standard deviation = 3 points

Using the empirical rule:

=85 - (3 × 3)

= 85 - 9

= 76

The given value of 76 points is 3 standard deviations below mean

Therefore;

the percent score between the given value of 76 points and the mean 85 points is:

99.7/2 = 49.85% ( since 99.7 data value lies within 3 standard deviation)

Also ; the percent of value above the mean score = 50%

Therefore, the probability that a student's score is greater than 76 points is

= (49.85 + 50 )%

= 99.85%

User LPD
by
3.9k points