Question

multiple choice at the end of the semester, mrs. johnson allows her students to drop their lowest test score. if jonah drops his lowest test score at the end of the semester, which of the following statements is most likely true? remember: removing an extreme value (outlier) has the greatest effect on the mean and range of a data set. a jonahs median test score will decrease. b jonahs average test score will increase. c the range of jonahs test scores will remain unchanged.

Explanation:

Step1: Understand effect of removing outlier

Removing lowest score (outlier) affects mean and range.

Step2: Analyze mean

The mean is the sum of all values divided by the number of values. Removing the lowest value increases the sum while decreasing the number of values slightly, which generally increases the mean.

Step3: Analyze median

The median is the middle - value. If the number of data points is odd, removing one value may or may not change the median depending on the position of the removed value. If the number of data points is even, the median is the average of two middle - values and may also not change.

Step4: Analyze range

The range is the difference between the highest and the lowest values. Removing the lowest value decreases the range.

Answer:

B. Jonah's average test score will increase.