Question
You have 4 distinct cubes and 2 distinct balls. Find the
number of ways to arrange them such that all 4 cubes are not placed together.Solution
Total = 6! = 720
Cubes together: Treat as 1 block + 2 balls = 3! = 6
Internal cube arrangements = 4! = 24
Together = 6 * 24 = 144
Required = 720 - 144 = 576
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