How to Calculate a Fraction of a Whole Number: Step-by-Step Math Guide

Understanding Fractions of Whole Numbers

• 🎯 The core concept is to find a portion of a given whole number, represented as a fraction.
• 💡 For example, calculating "3/4 of 8" involves multiplying the fraction by the whole number.

Method 1: Direct Multiplication

• ➕ To multiply a fraction by a whole number, first write the whole number as a fraction by placing it over one (e.g., 8 becomes 8/1).
• ✖️ Then, multiply the numerators together and the denominators together.
• ➗ Finally, divide the resulting numerator by the denominator to find the answer.
• 📊 Example: For 3/4 of 8, multiply (3/4) * (8/1) = 24/4, which simplifies to 6.

Method 2: Simplification Before Multiplication

• 🔍 An alternative approach is to simplify before multiplying.
• ✍️ Rewrite the whole number as a product of factors, where one factor can cancel out with the denominator of the fraction.
• ✂️ Cancel out the common factor between the numerator of the fraction and the whole number (or its factors).
• ✨ Multiply the remaining numbers to get the simplified answer.
• 📊 Example: For 3/5 of 20, rewrite 20 as 5 * 4. Cancel the 5s, leaving 3 * 4 = 12.

Practice Problems

• 📝 The video encourages practice with problems like "2/3 of 12" and "5/7 of 28".
• ✅ Solving 2/3 of 12: (2/3) * (12/1). Simplify 12 to 4*3, cancel the 3s, leaving 2 * 4 = 8.
• ✅ Solving 5/7 of 28: (5/7) * (28/1). Simplify 28 to 7*4, cancel the 7s, leaving 5 * 4 = 20.