Statistics students were asked to fill a one-cup measure with raisin bran, tap the cup lightly on the counter three times to settle the contents, if necessary add more raisin bran to bring the contents exactly to the one-cup line, spread the contents on a large plate, and count the raisins. The 13 students who chose Kellogg's Raisin Bran obtained the results shown below.

(a) Use Excel to calculate the mean, median, mode, and midrange.

(b) Which is the best measure of central tendency, and why?

(c) Calculate the standard deviation and coefficient of variation.

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