Question: fractions and mixed numbers
1. Let's start by understanding what fractions and mixed numbers are.
2. A fraction is a number that represents a part of a whole and is written as $\frac{a}{b}$ where $a$ is the numerator and $b$ is the denominator.
3. A mixed number is a whole number combined with a fraction, for example, $2 \frac{1}{3}$.
4. To convert a mixed number to an improper fraction, use the formula:
$$\text{Improper fraction} = \frac{(\text{whole number} \times \text{denominator}) + \text{numerator}}{\text{denominator}}$$
5. For example, convert $2 \frac{1}{3}$ to an improper fraction:
$$\frac{(2 \times 3) + 1}{3} = \frac{6 + 1}{3} = \frac{7}{3}$$
6. To convert an improper fraction back to a mixed number, divide the numerator by the denominator:
$$7 \div 3 = 2 \text{ remainder } 1$$
So, the mixed number is $2 \frac{1}{3}$.
7. When adding or subtracting fractions, make sure the denominators are the same. If not, find the least common denominator (LCD).
8. For example, add $\frac{1}{4} + \frac{1}{6}$:
- Find LCD of 4 and 6, which is 12.
- Convert fractions: $\frac{1}{4} = \frac{3}{12}$ and $\frac{1}{6} = \frac{2}{12}$.
- Add: $\frac{3}{12} + \frac{2}{12} = \frac{5}{12}$.
9. Simplify fractions by dividing numerator and denominator by their greatest common divisor (GCD).
10. For multiplication, multiply numerators and denominators directly:
$$\frac{a}{b} \times \frac{c}{d} = \frac{a \times c}{b \times d}$$
11. For division, multiply by the reciprocal:
$$\frac{a}{b} \div \frac{c}{d} = \frac{a}{b} \times \frac{d}{c} = \frac{a \times d}{b \times c}$$
This covers the basics of fractions and mixed numbers.