Addition of Positive Decimal Fractions
Master the art of adding decimal numbers with confidence!
What Are Decimal Fractions?
A decimal fraction is a number that has two parts separated by a decimal point:
- Whole number part — to the left of the decimal point
- Fractional part — to the right of the decimal point
Example: In 3.75
• 3 is the whole number part
• 75 is the fractional part (75 hundredths)
• 3 is the whole number part
• 75 is the fractional part (75 hundredths)
Place Value Chart
Interactive visualization — available in the full lesson
Each position has a specific value based on powers of 10
The Golden Rule: Align the Decimal Points!
✓ CORRECT Way
12.50 + 3.75 ------- 16.25
Decimal points are aligned vertically!
✗ WRONG Way
12.5 + 375 ------- 387.5 ← WRONG!
Numbers not aligned by decimal point!