68-95-99.7 Rule and Normal Distribution Question. I need help solving this question. It is on my final exam review. I was given the answer but i do not know how to solve it. 
1) Not everyone pays the same price for the same model of a car. Suppose the price of a car is normally distributed. The mean price of a particular model of a new car is 22,000 and the standard deviation is 750. Use both the 68-95-99.7 Rule and Normal Distribution to find the percentages of buyers who paid more than 22,750? 
ANS: P(x>22,750) = 0.16
 Normal Distribution
 P(x>22,750) = 0.1587


Trivial problem if you remember what the rule means: 68% is the proportion of buyers who pay within 1 standard deviation of the mean. 32% pay more or less, so 16% pay more. 22750 is 1 standard deviation above the mean.
