Question

1. I recently asked 100 middle school students to complete a statistics test. The mean score on the test was 30 points with a standard deviation of 5 points. The scores followed a normal distributions. Using this information, calculate the following:

1. What is the probability a student earned a score of 45 points or less?
   P (score < 45 points) =

2. What is the probability a student earned a score higher than 30 points?
   P(score > 30) =

3. What is the probability a student earned a score between 25 and 45 points?
   P (25 points < score < 45 points) =

4. I want to know the cutoff value for the upper 10%. What score separates the lower 90% of scores from the upper 10%?
   P (score < _______) = 90% or 0.90 cumulative area to the left

5. I want to know the cutoff values for the lowest 25%.

P (score < ________) = 25% or 0.25 cumulative area to the left

6. I would also like to know the cut off values for the highest 25%.
   P (score > _______) = 25% or 0.25 cumulative area to the right

5. I want to know the cutoff values for the lowest 25%.

P (score < ________) = 25% or 0.25 cumulative area to the left

6. I would also like to know the cut off values for the highest 25%.
   P (score > _______) = 25% or 0.25 cumulative area to the right

Answer 1