Across
1
Middle value in an ordered dataset
2
Closed shape with straight sides
5
System of ordered marks for measuring
6
Line crossing from corner to corner
7
Collection of distinct elements
10
Part of a circle's circumference
Down
2
Total distance around a shape
3
Single numeral from 0 to 9
4
Lines that never intersect
5
Exact correspondence on both sides
8
Part of a whole number
9
Number with digits after a point