Across
1
Rectangle with four equal sides
2
Closed shape with straight sides
3
Collection of distinct elements
5
System of ordered marks for measuring
9
Middle value in an ordered dataset
10
Math using letters for unknown values
11
Single numeral from 0 to 9
12
Split into equal parts
13
Parts per hundred
Down
2
Number greater than zero
4
Part of a circle's circumference
6
Power to which a number is raised
7
Value that does not change
8
Difference between highest and lowest values