Painted cube, one face showing
A cube is painted on its outside and cut into 27 unit cubes. You pick one unit cube at random, roll it like a die, and see that the face on top is painted. What is the probability that you picked a corner cube? (to 4 decimals)
Show hints (2)+
- Every (cube, face) pair is equally likely to end up on top - so condition on landing on a painted face.
- Count painted faces by type: corners , edges , centres - 54 in total.
Answer
Reveal answer →Final answer
0.4444 (± 0.005)
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