Best method for scrolling wgs?

To find out the expectancy of your scrolling business simply do this: multiply each of your case's result by the probability of them happening, then add all them up and you have your expected average income.

Yeah, like so:
first fail = throw away = loss of 7m
0.40 chance *( -7) = -2.80m

first pass, second fail, sell for 2m(?)** = loss of 12m
0.60*0.40*(-12) = 0.24 * (-12) = -2.88m

first pass, second pass, third fail, sell for 4m(?)** = loss of 17m
0.60*0.60*0.40*-17 = 0.144 * (-17) = -2.45

first pass, second pass, third pass, fourth fail, scroll again (if 6 atk, sell for 10m(?)** = loss of 25m. if 8 atk sell for 40m = profit of 5m)
0.60*0.60*0.60*0.40*0.40*(-25) = 0.03456 * (-25) = -.86m
0.60*0.60*0.60*0.40*0.60*5 = 0.0518 * 5 = +.26m

0.60*0.60*0.60*0.60*0.40*5 = 0.0518 * 5 = +.26m

all pass, sell wg for 130-140m = profit of 95m - 105m

0.60*0.60*0.60*0.60*0.60*135 = 0.0776*100 = +7.76

Check that all probabilities add to 1: (.40+.24+.144+.03456+.0518+.0518+.0776) = .99976

Typical result: (-2.80-2.88-2.45-0.86+0.26+0.26+7.76) = -0.7m average LOSS assuming given prices

Also aren't the scrolls usually 8m or more? Doesn't look like an easy get rich plan to me.