A school is considering a major change to its grading system. It recognizes that even though students work hard and do well for most of the grading period, sometimes students get overwhelmed and do poorly on one test, which affects their overall grades.

Which measure of central tendency does the school likely already use that causes one low score to negatively affect a student's overall grade?

Mean Central Tendency

Explanation:

Central tendency means the measures in which we use in finding  the average value of a statistical series of quantitative data.The mean gives the arithmetic average of a group of scores that is the scores from a data are totaled and divided by the number of scores. Mean as a measure for central tendency is   easy to understand, calculate and utilizes all scores of a distribution, However,  it tends to be affected by extreme scores giving absurd negative values for example, a couple of extremely low scores can skew the mean so that the average score appears much more lower than most of the scores actually are.

Here, Even though students work hard and do well for most of the grading period, sometimes students get overwhelmed and do poorly on one test, which affects their overall grades-->this is because mean central tendency can give negative absurd values for extreme scores ( in this case, low scores ) in its observation, affecting a student's overall grade.

b) to encourage free trade

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