Easy
2
+18
HALVE
−1
×3
+5
÷8
SQUARE
÷2
+3
Medium
19
×5
−6
×2
−18
DOUBLE
−5
×1/3
+7
×1/4
Hard
107
+3
÷10
−1
×11/5
HALVE
SQUARE
×31/2
+42
×25%
There are two versions that can be printed, a default one, and one that requires less ink (no objectives or rules, and no lines).