UB Coding Conundrum

Problems

Name Solved / Tries Average tries Average tries to solve
A Goat Rope 4/12 (33%) 2.00 1.25
B Disastrous Doubling 0/22 (0%) 5.50 --
C Take Two Stones 6/11 (55%) 1.83 1.83
D Life Forms 0/5 (0%) 5.00 --
E Exact Change 0/8 (0%) 2.00 --
F GCDs 0/4 (0%) 4.00 --
G Zamka 5/20 (25%) 3.33 1.60
H Magic Checkerboard 0/13 (0%) 6.50 --
I Intersecting Rectangles 0/3 (0%) 3.00 --