Easy
15
+6
÷7
SQUARE
×5
+11
HALVE
−10
×3
+15
Medium
18
HALVE
−1
×1/4
×7
−5
SQUARE
DOUBLE
+6
×3/8
Hard
54
−10
×7/11
×3
×25%
+13
×4
+18
HALVE
+21
There are two versions that can be printed, a default one, and one that requires less ink (no objectives or rules, and no lines).