Question: Calculate $1 \frac{2}{7} + 2 \frac{2}{3}$
Give your answer as a mixed number in its simplest form.
1. **State the problem:** We need to calculate the sum of the mixed numbers $1 \frac{2}{7}$ and $2 \frac{2}{3}$ and express the answer as a mixed number in simplest form.
2. **Convert mixed numbers to improper fractions:**
$$1 \frac{2}{7} = \frac{1 \times 7 + 2}{7} = \frac{7 + 2}{7} = \frac{9}{7}$$
$$2 \frac{2}{3} = \frac{2 \times 3 + 2}{3} = \frac{6 + 2}{3} = \frac{8}{3}$$
3. **Find a common denominator:**
The denominators are $7$ and $3$. The least common denominator (LCD) is $21$.
4. **Convert fractions to have the LCD:**
$$\frac{9}{7} = \frac{9 \times 3}{7 \times 3} = \frac{27}{21}$$
$$\frac{8}{3} = \frac{8 \times 7}{3 \times 7} = \frac{56}{21}$$
5. **Add the fractions:**
$$\frac{27}{21} + \frac{56}{21} = \frac{27 + 56}{21} = \frac{83}{21}$$
6. **Convert the improper fraction back to a mixed number:**
Divide $83$ by $21$:
$$83 \div 21 = 3 \text{ remainder } 20$$
So,
$$\frac{83}{21} = 3 \frac{20}{21}$$
7. **Simplify the fraction if possible:**
The fraction $\frac{20}{21}$ is already in simplest form because $20$ and $21$ have no common factors other than $1$.
**Final answer:**
$$3 \frac{20}{21}$$