The state's smallest animal is a red-tailed gerbil, with a mean weight of 2.5 grams and a standard deviation of 0.25 grams. Assuming that the weights are normally distributed, find the probability of randomly selecting a gerbil that weighs
a. between 1.0 and 2.0 grams
b. between 1.6 and 2.2 grams
c. more than 2.2 grams
The solution shows how to use z-score to find the probability of the weight range of gerbil, which is normally distributed.