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प्रश्न
Find the number of words formed by permuting all the letters of the following words:
PAKISTAN
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उत्तर
This word consists of 8 letters that include two As.
The total number of words is the number of arrangements of 7 things, of which 2 are similar to one kind.
⇒\[\frac{8!}{2!}\]= 20160
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