Romang67 wrote:
Note that the spread of graph Y appears smaller than the spread of graph X. This tells us that the standard deviation of X is greater than the standard deviation of Y.
A: We don't know anything about the range. It appears that they are roughly equal, based on the width of the two graphs.
B: Based on the graphs, it does indeed appears that more of population Y is closer to the mean of the graph. This fits with what we said about the spread before. If the spread is smaller, more of the population would be closer to the mean.
C: As stated in the beginning, graph X has greater spread, so it has a greater standard deviation than Y.
If SD of Town x is greater than Town y, then range of Town x should also be greater than that of Town y. Because the range of a normal distribution is 6xSD