The word "NATURAL" consists of 7 letters: N, A, T, U, R, A, L.
First, let's identify the vowels in the word:
- The vowels in "NATURAL" are A, A, and U.
Now, we count the total number of vowels:
- There are 3 vowels (A, A, and U).
Next, we find the total number of letters in the word "NATURAL":
- There are 7 letters in total.
The probability of randomly selecting a vowel is given by the ratio of the number of vowels to the total number of letters:
\[ \text{Probability} = \frac{\text{Number of Vowels}}{\text{Total Number of Letters}} = \frac{3}{7} \]
Thus, the probability that the letter chosen is a vowel is:
\[ \frac{3}{7} \]