What is Dividing a Decimal by 10?

S1-SA2-1121

Grade Level:

Class 5

Maths, Finance, Computing, AI

Definition

What is it?

Dividing a decimal by 10 means making the number ten times smaller. When you divide a decimal by 10, the decimal point moves one place to the left. This is a quick way to find one-tenth of a number.

Simple Example

Quick Example

Imagine a packet of biscuits costs Rs 125.50. If there's a special offer where you get 1/10th of the price back as a discount, how much discount do you get? You divide 125.50 by 10, which means the decimal point moves one place left, giving you Rs 12.55 discount.

Worked Example

Step-by-Step

Let's divide 45.6 by 10.

Step 1: Write down the decimal number: 45.6
---Step 2: Identify the decimal point. In 45.6, it's between 5 and 6.
---Step 3: To divide by 10, move the decimal point one place to the left.
---Step 4: Moving the decimal point one place left from its original position (between 5 and 6) brings it between 4 and 5.
---Step 5: The new number becomes 4.56.

So, 45.6 divided by 10 is 4.56.

Why It Matters

Understanding how to divide decimals by 10 is super important! It's used in finance to calculate interest or discounts, in computing for scaling data, and even in AI for adjusting model parameters. Future engineers, data scientists, and business owners use this skill daily.

Common Mistakes

MISTAKE: Moving the decimal point to the right instead of the left. For example, changing 3.4 to 34. | CORRECTION: Always remember, dividing by 10 makes the number smaller, so the decimal point must move to the LEFT.

MISTAKE: Forgetting to add a zero if there are no digits before the decimal point after moving it. For example, changing .5 to 5. | CORRECTION: If the decimal point moves past all digits, add a zero in front of it to hold the place. For example, 0.5 divided by 10 becomes 0.05.

MISTAKE: Confusing division by 10 with multiplication by 10. | CORRECTION: Division by 10 moves the decimal LEFT (makes smaller). Multiplication by 10 moves the decimal RIGHT (makes larger).

Practice Questions

Try It Yourself

QUESTION: What is 78.2 divided by 10? | ANSWER: 7.82

QUESTION: A 100-meter race track is divided into 10 equal parts. How long is each part if a segment is 15.5 meters and you want to find 1/10th of that segment? | ANSWER: 1.55 meters

QUESTION: If a water bottle contains 1.75 litres of water, and you pour out one-tenth of it, how much water did you pour out? | ANSWER: 0.175 litres

MCQ

Quick Quiz

What is 205.3 divided by 10?

2053

20.53

2.053

205.3

The Correct Answer Is:

When dividing by 10, the decimal point moves one place to the left. In 205.3, moving the decimal point one place left makes it 20.53.

Real World Connection

In the Real World

Imagine you're checking your mobile data usage. If your phone shows you've used 7.8 GB and you want to know what one-tenth of that usage is (maybe for a specific app), you'd divide 7.8 by 10 to get 0.78 GB. This helps you track usage more precisely.

Key Vocabulary

Key Terms

DECIMAL: A number that includes a decimal point, like 3.5 | DECIMAL POINT: The dot that separates the whole number part from the fractional part | PLACE VALUE: The value of a digit based on its position in a number, like the 'tens' place or 'tenths' place | DIVIDE: To split a number into equal parts

What's Next

What to Learn Next

Great job learning about dividing by 10! Next, you should explore 'Dividing a Decimal by 100'. It builds on this concept, as you'll learn to move the decimal point two places to the left, making numbers even smaller.