1. **State the problem:** We want to find the probability that the first letter in a random arrangement of the letters in "ARIZONA" is A.
2. **Count total letters and repetitions:** The word "ARIZONA" has 7 letters: A, R, I, Z, O, N, A. Note that A appears twice.
3. **Total number of distinct arrangements:** The total number of ways to arrange these letters is given by the formula for permutations of multiset:
$$\frac{7!}{2!}$$
where 7! is the factorial of 7 and 2! accounts for the two identical A's.
4. **Number of favorable arrangements (first letter is A):** Fix the first letter as A. Now arrange the remaining 6 letters: A, R, I, Z, O, N.
The number of ways to arrange these is:
$$6! / 1! = 6!$$
since there is only one A left.
5. **Calculate the probability:**
$$\text{Probability} = \frac{\text{Number of favorable arrangements}}{\text{Total number of arrangements}} = \frac{6!}{\frac{7!}{2!}}$$
6. **Simplify the expression:**
$$\frac{6!}{\frac{7!}{2!}} = \frac{6!}{\frac{7 \times 6!}{2}} = \frac{6!}{7 \times 6! / 2} = \frac{6! \times 2}{7 \times 6!} = \frac{2}{7}$$
7. **Final answer:**
$$\boxed{0.286}$$
The probability that the first letter is A is approximately 0.286.
Probability First A 1B09Fd
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