Question: Add. begin fraction 7 over b + 3 end fraction + begin fraction 4 over b + 3 end fraction
1. **State the problem:**
Add the two fractions $$\frac{7}{b+3} + \frac{4}{b+3}$$.
2. **Formula and rules:**
When adding fractions with the same denominator, add the numerators and keep the denominator the same:
$$\frac{a}{c} + \frac{b}{c} = \frac{a+b}{c}$$
3. **Apply the formula:**
Since both fractions have the same denominator $$b+3$$, add the numerators:
$$\frac{7}{b+3} + \frac{4}{b+3} = \frac{7+4}{b+3}$$
4. **Simplify the numerator:**
$$\frac{7+4}{b+3} = \frac{11}{b+3}$$
5. **Final answer:**
$$\boxed{\frac{11}{b+3}}$$
This is the sum of the two fractions.