Probabilities in painted cube...
A wooden cube - after being painted all over - has been cut into smaller equal cubes. These were thoroughly mixed in a bag, from which one was produced and tossed. What is the probability that a painted side turned up? The answer can be written as where and are coprime positive integers. Find .
not original problem
The answer is 11.
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1 solution
A cube is painted cut the cube into 10×10×10, smaller cubes. Following the foregoing pattern, we eventually arrive at
there are 8 cubes with 3 paint face, 96 cubes with 2 painted face, 384 cube with one painted face and the rest has no paint on them
them the probability is
(8/1000)(3/6) + (96/1000)(2/6)+ (384/1000)(1/6) = 1/10
m = 1 and n=10 then m+n=11