1. **State the problem:** Solve the expression $$\left(\frac{2}{7} + \frac{1}{3}\right) + \frac{2}{3}$$ using properties and mental math.
2. **Recall the formula and rules:** To add fractions, find a common denominator, then add the numerators.
3. **Find common denominator for the first parentheses:**
$$\text{LCM of }7 \text{ and } 3 = 21$$
4. **Convert fractions:**
$$\frac{2}{7} = \frac{2 \times 3}{7 \times 3} = \frac{6}{21}$$
$$\frac{1}{3} = \frac{1 \times 7}{3 \times 7} = \frac{7}{21}$$
5. **Add inside parentheses:**
$$\frac{6}{21} + \frac{7}{21} = \frac{6+7}{21} = \frac{13}{21}$$
6. **Add the remaining fraction:**
$$\frac{13}{21} + \frac{2}{3}$$
7. **Find common denominator for $$\frac{13}{21}$$ and $$\frac{2}{3}$$:**
$$\text{LCM of }21 \text{ and } 3 = 21$$
8. **Convert $$\frac{2}{3}$$:**
$$\frac{2}{3} = \frac{2 \times 7}{3 \times 7} = \frac{14}{21}$$
9. **Add the fractions:**
$$\frac{13}{21} + \frac{14}{21} = \frac{13+14}{21} = \frac{27}{21}$$
10. **Simplify the fraction:**
$$\frac{27}{21} = \frac{\cancel{3} \times 9}{\cancel{3} \times 7} = \frac{9}{7}$$
11. **Final answer:**
$$\boxed{\frac{9}{7}}$$
This is an improper fraction and can also be written as $$1 \frac{2}{7}$$.
Fraction Addition E4A9Ef
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