The marks distribution (in %) of students of a class was found to be symmetric. Results revealed that 25 % of the students scored 78% or more while one-fourth of these students scored 30% or less. Determine the mean score of these students. Also find the 10% trimmed mean if possible.
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We have a symmetric distribution of student scores. 25% of students scored 78% or more. One-fourth of these students (which is 25% of 25% = 6.25% of all students) scored 30% or less. Show more…
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