Operation on Rational Numbers Grade 7 .pptx

Mathematics

1. Operation on Rational Numbers

2. 1. Definition of Rational Numbers A rational number is any number that can be written as a/b, where a and b are integers and b ≠ 0. Includes: Whole numbers (e.g., 5 = 5/1) Integers (e.g., -2 = -2/1) Fractions (e.g., 3/4) Terminating decimals (e.g., 0.75) Repeating decimals (e.g., 0.333...) Examples: 2/3, -5, 0.6, -1.25, 7

3. 2. Operations on Rational Numbers Use number lines, models, or step-by-step explanation. A. Addition/Subtraction Convert to same denominator if fractions. Watch the signs if dealing with integers. Example 1: 3/4 + 1/2 = ?

4. 2. Operations on Rational Numbers Use number lines, models, or step-by-step explanation. A. Addition/Subtraction Convert to same denominator if fractions. Watch the signs if dealing with integers. Example 1: 3/4 + 1/2 = ? → Convert 1/2 to 2/4

5. 2. Operations on Rational Numbers Use number lines, models, or step-by-step explanation. A. Addition/Subtraction Convert to same denominator if fractions. Watch the signs if dealing with integers. Example 1: 3/4 + 1/2 = ? → Convert 1/2 to 2/4 → 3/4 + 2/4 = 5/4 or 1 1/4

6. 2. Operations on Rational Numbers Use number lines, models, or step-by-step explanation. A. Addition/Subtraction Convert to same denominator if fractions. Watch the signs if dealing with integers. Example 1: 3/4 + 1/2 = ? → Convert 1/2 to 2/4 → 3/4 + 2/4 = 5/4 or 1 1/4

7. 2. Operations on Rational Numbers Use number lines, models, or step-by-step explanation. A. Addition/Subtraction Convert to same denominator if fractions. Watch the signs if dealing with integers. Example 2: -2 + 5 = 3 -7 - 3 = -10

8. 2. Operations on Rational Numbers B. Multiplication Multiply numerators and denominators. Simplify if possible. Example: (2/3) × (4/5) = (2×4)/(3×5) = 8/15 Sign Rule: Same sign → positive Different signs → negative

9. C. Guided Practice (15 minutes) 1. 3/4 + 5/6 2. -2 – 4 3. 1/2 + 3/4 4. 3/5 × 10/9 5. -10 - (-12)

10. Problem 1. Ana spent 3/4 of her allowance on food and 1/6 on transportation. What part of her allowance did she spend in total? 2. Lara drank 2/5 liter of juice in the morning and 3/10 liter in the afternoon. How much juice did she drink in total?