1. **Problem Statement:** Jamie has a probability of hitting a target as $\frac{1}{3}$. We want to find the attempt number $n$ when he hits the target for the first time, given the probability of this event is $\frac{64}{2187}$.
2. **Formula Used:** The probability that the first success occurs on the $n$th attempt in a geometric distribution is given by:
$$P(X=n) = (1-p)^{n-1} p$$
where $p$ is the probability of success on each attempt.
3. **Apply the values:** Here, $p = \frac{1}{3}$, so the probability of failure is $1-p = \frac{2}{3}$.
4. **Set up the equation:**
$$\left(\frac{2}{3}\right)^{n-1} \times \frac{1}{3} = \frac{64}{2187}$$
5. **Isolate the exponential term:**
$$\left(\frac{2}{3}\right)^{n-1} = \frac{64}{2187} \times 3 = \frac{192}{2187}$$
6. **Simplify the right side:**
Note that $64 = 2^6$ and $2187 = 3^7$, so:
$$\frac{192}{2187} = \frac{64 \times 3}{3^7} = \frac{2^6 \times 3}{3^7} = 2^6 \times 3^{1-7} = 2^6 \times 3^{-6}$$
7. **Rewrite the left side:**
$$\left(\frac{2}{3}\right)^{n-1} = 2^{n-1} \times 3^{-(n-1)}$$
8. **Equate powers:**
$$2^{n-1} \times 3^{-(n-1)} = 2^6 \times 3^{-6}$$
9. **Match exponents for each base:**
For base 2: $n-1 = 6$
For base 3: $-(n-1) = -6$
Both give $n-1 = 6$.
10. **Solve for $n$:**
$$n = 6 + 1 = 7$$
**Final answer:** $n = 7$
Geometric Probability 373372
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