What is Dividing a Decimal by a Whole Number?

S1-SA2-0278

Grade Level:

Class 5

Maths, Finance, Science, Computing, AI

Definition

What is it?

Dividing a decimal by a whole number means splitting a number that has a decimal point into equal parts. It helps us find out how much each part gets when we share something that isn't a whole amount.

Simple Example

Quick Example

Imagine you bought a packet of biscuits for Rs 24.50 and want to share the cost equally with your friend. You need to divide Rs 24.50 by 2 to find out how much each of you pays. Each person would pay Rs 12.25.

Worked Example

Step-by-Step

Let's divide 15.6 by 3.

Step 1: Set up the division like you would with whole numbers. Write 15.6 inside and 3 outside.

Step 2: Start dividing the whole number part (15) by 3. 15 divided by 3 is 5.

Step 3: Write 5 in the quotient above the 5 in 15.6. Subtract 3 x 5 = 15 from 15, which leaves 0.

Step 4: Bring down the decimal point from the dividend (15.6) straight up into the quotient.

Step 5: Bring down the next digit (6) from the dividend. Now you have 6.

Step 6: Divide 6 by 3. 6 divided by 3 is 2.

Step 7: Write 2 in the quotient after the decimal point. Subtract 3 x 2 = 6 from 6, which leaves 0.

Answer: So, 15.6 divided by 3 is 5.2.

Why It Matters

Understanding this helps you calculate averages, split bills, and even understand science experiments. Engineers use it to divide measurements, and financial analysts use it to calculate per-unit costs, which can lead to careers in finance or even space science at ISRO.

Common Mistakes

MISTAKE: Forgetting to place the decimal point in the quotient directly above the decimal point in the dividend. | CORRECTION: Always bring the decimal point straight up into the quotient before continuing with the division.

MISTAKE: Treating the decimal number as a whole number throughout the division and adding the decimal point at the very end randomly. | CORRECTION: Divide the whole number part first, place the decimal point, then continue dividing the decimal part.

MISTAKE: Not adding a zero in the quotient if the digit you bring down is smaller than the divisor. | CORRECTION: If the current part of the dividend is smaller than the divisor, write a 0 in the quotient and bring down the next digit.

Practice Questions

Try It Yourself

QUESTION: A 10.8-meter roll of cloth is cut into 4 equal pieces. How long is each piece? | ANSWER: 2.7 meters

QUESTION: You have Rs 56.75 and want to divide it equally among 5 friends. How much money does each friend get? | ANSWER: Rs 11.35

QUESTION: A car travels 123.6 km in 6 hours. If it travels at a constant speed, what distance does it cover in 1 hour? | ANSWER: 20.6 km

MCQ

Quick Quiz

What is 34.5 divided by 5?

6.9

0.69

6.5

The Correct Answer Is:

To divide 34.5 by 5, first divide 34 by 5 to get 6 with a remainder of 4. Place the decimal point. Then combine the remainder 4 with 5 to make 45, and divide 45 by 5 to get 9. So the answer is 6.9.

Real World Connection

In the Real World

When you buy mobile data, say 10.5 GB for a month, and want to use it equally over 3 weeks, you'd divide 10.5 by 3 to know your weekly data limit. This helps you manage your internet usage, just like how delivery apps like Zepto might calculate average delivery times per driver.

Key Vocabulary

Key Terms

DECIMAL: A number that has a fractional part, shown by a decimal point, like 3.5 | WHOLE NUMBER: A number without fractions or decimals, like 1, 2, 3 | DIVIDEND: The number being divided (the number inside the division symbol) | DIVISOR: The number by which another number is divided (the number outside the division symbol) | QUOTIENT: The result of a division.

What's Next

What to Learn Next

Great job with this concept! Next, you can explore 'Dividing a Decimal by a Decimal'. This builds on what you've learned and will help you solve even more complex problems involving money, measurements, and everyday calculations.