The table shows data from local day-care centers, representing the number of children in attendance (x) and daily food costs in dollars (y). x y x2 xy 16 45 256 720 22 58 484 1,276 28 73 784 2,044 32 94 1,024 3,008 45 141 2,025 6,345 ∑x=143 ∑y=411 ∑x2=4,573 ∑xy=13,393 Which regression equation correctly models the data? y = 2.87x + 0.12 y = 2.87x + 11.85 y = 3.39x – 14.75 y = 3.39x – 9.24

1. why is a frequency distribution useful? it allows researchers to see the "shape" of the data. it tells researchers how often the mean occurs in a set of data. it can visually identify the mean. it ignores outliers. 2. the is defined by its mean and standard deviation alone. normal distribution frequency distribution median distribution marginal distribution 3. approximately % of the data in a given sample falls within three standard deviations of the mean if it is normally distributed. 95 68 34 99 4. a data set is said to be if the mean of the data is greater than the median of the data. normally distributed frequency distributed right-skewed left-skewed