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A3x4x5 rectangular cuboid (e.g. a brick) is painted blue and cut into 1x1 cubes. what is the expected value for the painted sides of a randomly selected cube?

Nine more than four times a number is the same as one less than twice the number. find the number?

The lengths of all sides of a triangle are integers when measured in decimeters. one of the sides has length of 1 dm and another of 3 dm. find the perimeter of the triangle.'