1. Stating the problem: Calculate $$\left( \frac{3}{4^{-1}} + \frac{5}{3^{-2}} \right) \cdot 19^{-1}$$ and determine which option (A, B, C, or D) matches the result.
2. Recall the rule for negative exponents: $$a^{-n} = \frac{1}{a^n}$$.
3. Simplify each term inside the parentheses:
$$\frac{3}{4^{-1}} = 3 \times 4^{1} = 3 \times 4 = 12$$
$$\frac{5}{3^{-2}} = 5 \times 3^{2} = 5 \times 9 = 45$$
4. Add the two results:
$$12 + 45 = 57$$
5. Simplify the multiplication by $$19^{-1}$$:
$$57 \cdot 19^{-1} = 57 \times \frac{1}{19} = \frac{57}{19}$$
6. Simplify the fraction $$\frac{57}{19}$$:
Since $$19 \times 3 = 57$$, we have
$$\frac{57}{19} = 3$$
7. Final answer: $$3$$, which corresponds to option B.
Fraction Exponent 41A3A9
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