Understanding Decimal Numbers
Decimals are numbers that have a whole number part and a fractional part separated by a decimal point.
When adding or subtracting decimals, the most important rule is to line up the decimal points! This ensures we're adding tenths to tenths, hundredths to hundredths, and so on.
Step-by-Step Guide
1️⃣ Write the numbers vertically and line up the decimal points
2️⃣ Add zeros if needed to make all numbers the same length
3️⃣ Add or subtract just like with whole numbers
4️⃣ Bring down the decimal point directly below in your answer
Let's Practice Together!
Example 1: Shopping Spree
Emma bought a toy for $12.75 and a book for $8.49. How much did she spend in total?
$
Tens
Ones
Tenths
Hundredths
Item 1
1
2
7
5
Item 2
0
8
4
9
Example 2: Measuring Length
A rope is 5.6 meters long. If we cut off 2.35 meters, how much rope remains?
Meters
Ones
Tenths
Hundredths
Original
5
6
0
Cut off
2
3
5
Parent Tips 🌟
- Money makes sense: Use shopping receipts or create a pretend store to practice adding and subtracting decimals with dollars and cents.
- Kitchen measurements: Involve your child in cooking where recipes often use decimal measurements (1.5 cups, 0.25 teaspoons).
- Sports statistics: Compare player stats (batting averages, race times) which often use decimals - great for real-world connections!