Question
Five toys out of which 2 are identical robots and the
rest are different action figures are to be arranged in a row. Find the number of arrangements in which the two robots are not placed together.Solution
Total number of arrangements = 5! = 120 ways
If we treat the 2 robots as one group, arrangements among themselves = 2! = 2 ways Total arrangements = 120/2 = 60 ways
Number of arrangements of remaining 4 items = 4! = 24 ways
Therefore, required number of ways = 60 – 24 = 36 ways
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