We need to find the number of ways to arrange the letters of the word INDIA so that the vowels appear only in the odd positions. Let's first understand the components of the word INDIA:
A 5-letter arrangement requires 5 positions. We need to identify which ones are odd and which are even:
The main condition is that the vowels must be placed in the odd positions. We have 2 vowels (I, A) and 3 available odd positions (1, 3, 5).
Therefore, there are 6 distinct ways to arrange the vowels I and A within the available odd positions (1st, 3rd, 5th).
To complete the arrangement, the 3 consonants (N, D, R) need to be placed in the remaining \( 5 - 2 = 3 \) positions. These remaining positions consist of the two even slots (2nd, 4th) and the one odd slot that was not occupied by a vowel. The number of ways to arrange these 3 consonants in the 3 remaining spots is \( P(3, 3) = 3! = 6 \). The total number of permutations for the word INDIA with vowels in odd positions would be the product of the ways to arrange vowels and the ways to arrange consonants (\( 6 \times 6 = 36 \)). However, the calculation specifically for placing vowels in odd positions yields 6.
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