Understanding Mixed Number Subtraction
Mixed numbers are numbers that have both whole numbers and
fractions.
When subtracting mixed numbers with different denominators, we need to find a common denominator first.
This makes the fractions compatible so we can subtract them easily!
Step-by-Step Guide
1️⃣ Convert the mixed numbers to improper fractions
2️⃣ Find a common denominator for the fractions
3️⃣ Subtract the numerators and keep the denominator
4️⃣ Simplify the result if possible
5️⃣ Convert back to a mixed number if needed
Let's Practice Together!
Example 1: Subtract \(2\frac{3}{4} - 1\frac{1}{2}\)
1. Convert to improper fractions:
\(2\frac{3}{4} = \frac{11}{4}\) and \(1\frac{1}{2} = \frac{3}{2}\)
2. Find common denominator (4):
\(\frac{11}{4} - \frac{6}{4} = \frac{5}{4}\)
3. Convert back to mixed number:
\(\frac{5}{4} = 1\frac{1}{4}\)
Final answer: \(1\frac{1}{4}\)
Example 2: Subtract \(3\frac{2}{5} - 1\frac{3}{4}\)
1. Convert to improper fractions:
\(3\frac{2}{5} = \frac{17}{5}\) and \(1\frac{3}{4} = \frac{7}{4}\)
2. Find common denominator (20):
\(\frac{17}{5} = \frac{68}{20}\) and \(\frac{7}{4} = \frac{35}{20}\)
3. Subtract numerators:
\(\frac{68}{20} - \frac{35}{20} = \frac{33}{20}\)
4. Convert back to mixed number:
\(\frac{33}{20} = 1\frac{13}{20}\)
Final answer: \(1\frac{13}{20}\)
Parent Tips 🌟
- Kitchen Math: Use measuring cups to demonstrate mixed numbers in real life - subtract 1½ cups from 2¾ cups of flour in a recipe.
- Visual Aids: Draw pizzas or pies divided into different fractions to show why common denominators are needed.
- Step Check: Have your child explain each step out loud - understanding why we convert to improper fractions is key!