1. **Stating the problem:** We will learn how to add, subtract, multiply, and divide fractions, which are common operations in grade 7 math.
2. **Important rules and formulas:**
- To add or subtract fractions, they must have the same denominator. Use the formula:
$$\frac{a}{b} \pm \frac{c}{d} = \frac{ad \pm bc}{bd}$$
- To multiply fractions, multiply the numerators and denominators:
$$\frac{a}{b} \times \frac{c}{d} = \frac{ac}{bd}$$
- To divide fractions, multiply by the reciprocal of the divisor:
$$\frac{a}{b} \div \frac{c}{d} = \frac{a}{b} \times \frac{d}{c} = \frac{ad}{bc}$$
3. **Example: Add $$\frac{2}{3}$$ and $$\frac{1}{4}$$**
- Find common denominator: $$3 \times 4 = 12$$
- Convert fractions:
$$\frac{2}{3} = \frac{2 \times 4}{3 \times 4} = \frac{8}{12}$$
$$\frac{1}{4} = \frac{1 \times 3}{4 \times 3} = \frac{3}{12}$$
- Add numerators:
$$\frac{8}{12} + \frac{3}{12} = \frac{8+3}{12} = \frac{11}{12}$$
4. **Example: Multiply $$\frac{2}{3}$$ by $$\frac{4}{5}$$**
- Multiply numerators and denominators:
$$\frac{2}{3} \times \frac{4}{5} = \frac{2 \times 4}{3 \times 5} = \frac{8}{15}$$
5. **Example: Divide $$\frac{3}{4}$$ by $$\frac{2}{5}$$**
- Multiply by reciprocal:
$$\frac{3}{4} \div \frac{2}{5} = \frac{3}{4} \times \frac{5}{2} = \frac{3 \times 5}{4 \times 2} = \frac{15}{8}$$
6. **Simplify fractions if possible:**
- For example, $$\frac{15}{8}$$ is already in simplest form.
This covers the basic operations with fractions for grade 7.
Fractions Operations 43926E
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