Easy
12
+2
HALVE
+8
×4
−11
÷7
+1
SQUARE
−15
Medium
16
HALVE
SQUARE
DOUBLE
+4
÷6
−1
÷7
+1
×1/2
Hard
29
+7
÷12
+2
×33/5
SQUARE
−2
×4/7
×25%
−5
There are two versions that can be printed, a default one, and one that requires less ink (no objectives or rules, and no lines).