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प्रश्न
Find the number of words formed by permuting all the letters of the following words:
EXERCISES
उत्तर
This word consists of 9 letters that include three Es and two Ss.
The total number of words is the number of arrangements of 9 things, of which 2 are similar to one kind and 2 are similar to the second kind.
⇒\[\frac{9!}{2!3!}\]= 30240
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