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प्रश्न
In how many ways can 5 children be arranged in a line such that two particular children of them are always together
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उत्तर
We consider the arrangements by taking 2 particular children together as one and hence the remaining 4 can be arranged in 4! = 24 ways.
Again two particular children taken together can be arranged in two ways.
Therefore, there are 24 × 2 = 48 total ways of arrangement.
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