7) 5 of the 9 pizzas have less than 200 calories, which represents a percentage of:
77.77% of the pizzas have less than 200 calories
12) Standard deviation measures the spread of the data, if you add data greater than the greater data in the given table it will increase the standard deviation as that data will increase the average distance from the mean which increases the standard deviation.
You can add the data of a pizza with 385 calories to increase the standard deviation
13) New calorie data adding 90 calories will be:
New mean: 331.3
New median: 271
14) yes, both change (in value) when you add cheese.
Mean change because all the data increase then the mean will increase, as the mean is the average of the data it increases if the data increases.
Median change in value (271) but not in pizza type (pepperoni still being the median) because all the data change but the order doesn't change as all data increases the same amount.