1. Calculate the volume of entire cube as if it was a solid rectangle:
Length x width x height=
20x16x12 = 3,940 cubic inches
2. Calculate the volume of the "missing"
Piece and subtract:
Length x width x height=
20x8x6 = 960 cubic inches
(notice you can find the height of the missing piece by subtracting 12-6)
So your answer is 3,940-960 = 2,980 cubic inches inside the steps
the probability of getting tails up is 30/50 or most likely
the probability of getting a blue marble is 18/5 or least likely
Type into your calculator (if you haven't already): log 54.
My result: was similar to yours.
Note, however, that we're supposed to round off these results to the nearest thousandths (not thousand).
Your 1.73239 would need to be rounded off to 1.732, with 2 being the nearest thousandths.