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# Mean and standard deviation.

The following table displays information on the abortion rate- the number of abortions per 1,000 women- for each U.S. state and the District of Columbia in 2000.
a. What are the mean and the standard deviation for the abortion rate for all states?
b. Using the information from (a), how many states fall more than 1 standard deviation above the mean? How does this number compare with the number expected form the theoretical normal curve distribution? Can you suggest anything these states have in common that might cause them to have higher abortion rates?
c. How many states fall more than 1 standard deviation below the mean? Is this number greater or lower than the expected value form the theoretical normal curve? Again, can you suggest any characteristics these states have in common that might cause them to have lower abortion rates?
d. Create a histogram of abortion rates for all 50 states and Washington, D.C. Does the distribution appear to be normal? Use this information to further explain why the number of states falling more than 1 standard deviation below the mean differs from the expected value.

(The abortion rates are in the attachment).