Across
1
Rectangular array of numbers
5
Sum divided by count
8
Number with digits after a point
Down
2
Collection of distinct elements
3
Distance from center to edge of circle
4
Exact correspondence on both sides
6
Parts per hundred
7
Three-sided polygon
9
Line segment connecting two circle points
10
Corner point of a polygon
11
Math using letters for unknown values
12
Rectangle with four equal sides