WBJEE · Maths · Permutation Combination
The number of words that can be written using all the letters of the word "IRRATIONAL' is
- A \(\frac{10 !}{(2 !)^{3}}\)
- B \(\frac{10 !}{(21)^{2}}\)
- C \(\frac{10 !}{2 !}\)
- D 10 !
Answer & Solution
Correct Answer
(A) \(\frac{10 !}{(2 !)^{3}}\)
Step-by-step Solution
Detailed explanation
These are 10 letters in the word IRRATIONAL in which these are \(2^{4} I, 2 \cdot R^{\prime}\) and \(2 \cdot A^{\prime}\) \(\therefore\) The total number of word \(s=\frac{10 !}{2 ! 2 ! 2 !}=\frac{10 !}{(21)^{3}}\)
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