64 = 4³
-216 = (-6)³
.008 = 0.2³ . . . . . . 1000 = 10³, 8 = 2³. This is 8/1000, so the cube of 2/10
1/64 = (1/4)³ . . . . . . the inverse of the first number
4 17/27 = 125/27 = (5/3)³
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You can see that it would be helpful to have memorized the cubes of small integers.
