Acube is painted red on all six sides, then cut into 125 smaller congruent cubes. a small cube is selected at random and rolled. what is the probability that it has a red side facing up?

125 = 5³ = 5 · 5 · 5 
Every side of a larger cube is cut into 25 congruent squares.
Number of sides of smaller cubes that are painted:  25 · 6 = 150
Number of all sides of 125 cubes: 125 · 6 = 750
Probability : P(A) = 150/750 = 1/5 = 0.2
probability is 0.2 or 20%