Easy
17
−5
HALVE
+7
×3
−4
÷5
−1
SQUARE
−8
Medium
20
−12
×9
×2/3
−3
÷9
SQUARE
DOUBLE
+6
×5/8
Hard
115
−11
÷13
−2
SQUARE
×25%
+41
×90%
×3
+26
There are two versions that can be printed, a default one, and one that requires less ink (no objectives or rules, and no lines).