-320. The negative sign represents loss. In all of the other cases, values are either being added or not changed at all.
I would say that the median is the best measure for the center as there are two major outliers (16 and 18)
Lets price of article = x
Tax is 8% of article = 0.08x
x+0.08x=7.02
1.08x=7.02
x=7.02/1.08
x=6.5
The retail price is $6.50.
She will use 3 rows of 3 squares, for a total of 9 squares.
Since the shape she is covering is a square, all of the sides are equal. If 3 square tiles fit across the width of the top, then 3 square tiles fit across the length of it as well. This makes 3 by 3, or 9 squares.