Across
1
Rectangular array of numbers
4
Part of a circle's circumference
5
Round shape with all points equidistant
7
Longest side of a right triangle
8
Number divisible only by 1 and itself
10
Parts per hundred
Down
2
Symbol representing unknown value
3
Difference between highest and lowest values
4
Reference line in a graph
6
Single numeral from 0 to 9
8
Total distance around a shape
9
Repeated addition