The seasonal output of a new experimental strain of pepper plants was carefully weighed. The mean weight per plant is 15.0 pounds, and the standard deviation of the normally distributed weights is 1.75 pounds. Of the 200 plants in the experiment, how many produced peppers weighing between 13 and 16 pounds?
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A. B. C. D. E.Explanation
z = (x-u)/sigma. z1 = 13 - 15/1.75 = -1.1429 and z2 = 16 - 15/1.75 = 0.5714. The respective areas for those z-values are 0.3729 and 0.2157. Since they are on opposite sides of the mean, we add them up to find the area in between which is 0.5886. Therefore, 0.5886*200 = 118.