Solve Decimal Addition: 0.5 + 0.9 Using Number Line Method

Q: Why do we need to carry over when adding decimals?

Just like with whole numbers, when digits add up to 10 or more, we write the ones digit and carry the tens digit to the next place value. In $ 0.5 + 0.9 $, we get 5 + 9 = 14, so we write 4 and carry 1.

Q: How does the number line help me understand this?

The number line shows the visual representation of addition! Start at 0.5, then jump 0.9 units to the right. You'll land at 1.4, which confirms our answer.

Q: What if I get confused about where to put the decimal point?

Remember: The decimal point in your answer goes directly below the decimal points in the numbers you're adding. This keeps everything in the correct place value!

Q: Can I add these numbers without lining them up vertically?

Yes! You can think of it as $ 0.5 + 0.9 = 5 + 9 $ tenths = 14 tenths = 1.4. But vertical alignment helps avoid mistakes with decimal placement.

Decimal Addition with Visual Number Lines

$0.5+0.9=$

❤️ Continue Your Math Journey!

We have hundreds of course questions with personalized recommendations + Account 100% premium

Step-by-step video solution

Watch the teacher solve the problem with clear explanations

00:00 Solve

00:03 We'll use long addition for calculation

00:09 We'll place the decimal point in the appropriate position

00:12 We'll start by adding the corresponding smallest digits

00:19 We'll place the units and remember to carry 1

00:29 We'll add 1 to this calculation, and place it

00:39 And this is the solution to the question

Step-by-step written solution

Follow each step carefully to understand the complete solution

Understand the problem

$0.5+0.9=$

Step-by-step solution

To solve the problem of adding $0.5$ and $0.9$ , we follow these steps:

Step 1: Write the numbers vertically and align the decimal points:

$\begin{array}{c} 0.5 \\ +0.9 \\ \hline \end{array}$

Step 2: Add the numbers starting from the rightmost digit:

The digit after the decimal in $0.5$ is $5$ , and in $0.9$ it is $9$ .
Adding these, $5 + 9 = 14$ . Write down $4$ and carry over $1$ .

Step 3: Add the numbers before the decimal point with the carryover:

Since $0.5$ has $0$ and $0.9$ has $0$ before the decimal, add these along with the carryover. $0 + 0 + 1 = 1$

Thus, when we perform the addition, we find the result is $1.4$ .

Therefore, the solution to the problem is $1.4$ .

Final Answer

1.4

Key Points to Remember

Essential concepts to master this topic

Alignment: Always line up decimal points when adding vertically
Technique: Add digits from right: 5 + 9 = 14, write 4 carry 1
Check: Use number line visualization to confirm $0.5 + 0.9 = 1.4$ ✓

Common Mistakes

Avoid these frequent errors

Ignoring the carry-over when digits sum to 10 or more
Don't add 5 + 9 = 14 and write 14 in the decimal place = 0.14! This ignores place value rules. When digits sum to 10 or more, always write the ones digit and carry the tens digit to the next column.

Practice Quiz

Test your knowledge with interactive questions

Choose the correct writing form:

FAQ

Everything you need to know about this question

Why do we need to carry over when adding decimals?

Just like with whole numbers, when digits add up to 10 or more, we write the ones digit and carry the tens digit to the next place value. In $0.5 + 0.9$ , we get 5 + 9 = 14, so we write 4 and carry 1.

How does the number line help me understand this?

The number line shows the visual representation of addition! Start at 0.5, then jump 0.9 units to the right. You'll land at 1.4, which confirms our answer.

What if I get confused about where to put the decimal point?

Remember: The decimal point in your answer goes directly below the decimal points in the numbers you're adding. This keeps everything in the correct place value!

Can I add these numbers without lining them up vertically?

Yes! You can think of it as $0.5 + 0.9 = 5 + 9$ tenths = 14 tenths = 1.4. But vertical alignment helps avoid mistakes with decimal placement.

Why is 1.5 wrong as an answer?

If you got 1.5, you likely forgot to carry over! When 5 + 9 = 14, you must write 4 in the tenths place and add the carried 1 to get 1.4, not 1.5.

🌟 Unlock Your Math Potential

Get unlimited access to all 18 Decimal Fractions - Basic questions, detailed video solutions, and personalized progress tracking.

📹

Unlimited Video Solutions

Step-by-step explanations for every problem

📊

Progress Analytics

Track your mastery across all topics

🚫

Ad-Free Learning

Focus on math without distractions

No credit card required • Cancel anytime