What is Multiplying by Five?

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Grade Level:

Pre-School – Class 2

All domains without exception

Definition

What is it?

Multiplying by five means adding the same number five times. It's a quick way to find the total when you have five equal groups or five times of something. Think of it as counting by fives.

Simple Example

Quick Example

Imagine you buy 5 packets of biscuits, and each packet costs ₹10. To find the total cost, you can add ₹10 five times (₹10 + ₹10 + ₹10 + ₹10 + ₹10). A faster way is to multiply 5 by ₹10, which gives you ₹50.

Worked Example

Step-by-Step

Let's say you have 5 friends, and each friend eats 3 samosas. How many samosas are eaten in total?

Step 1: Understand the problem. We have 5 groups (friends) and each group has 3 items (samosas).
---Step 2: Write it as a multiplication problem: 5 x 3.
---Step 3: You can think of it as adding 3 five times: 3 + 3 + 3 + 3 + 3.
---Step 4: Add the numbers: 3 + 3 = 6. Then 6 + 3 = 9. Then 9 + 3 = 12. Then 12 + 3 = 15.
---Step 5: So, 5 x 3 = 15.
Answer: A total of 15 samosas are eaten.

Why It Matters

Understanding multiplication by five helps you quickly calculate costs, quantities, and measurements in daily life. It's a fundamental skill used by shopkeepers, engineers calculating materials, and even chefs measuring ingredients. Mastering it makes many calculations faster and easier.

Common Mistakes

MISTAKE: Confusing multiplication by five with adding five to a number (e.g., thinking 3 x 5 is 3 + 5 = 8) | CORRECTION: Remember multiplication means repeated addition of the number, not just adding five to it. 3 x 5 means 3 added 5 times (3+3+3+3+3).

MISTAKE: Incorrectly counting by fives (e.g., 5, 10, 16, 20...) | CORRECTION: Practice counting by fives regularly: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50. This helps build fluency.

MISTAKE: Forgetting that multiplying any number by zero gives zero (e.g., thinking 0 x 5 = 5) | CORRECTION: Any number multiplied by zero is always zero. If you have 0 groups of 5, you have nothing.

Practice Questions

Try It Yourself

QUESTION: If one cricket ball costs ₹50, how much will 5 cricket balls cost? | ANSWER: ₹250

QUESTION: A bus travels 5 km in one hour. How many kilometers will it travel in 5 hours, if it maintains the same speed? | ANSWER: 25 km

QUESTION: You have 5 boxes, and each box contains 8 mangoes. If you give away 10 mangoes, how many mangoes are left? | ANSWER: 30 mangoes

MCQ

Quick Quiz

What is the result of 7 multiplied by 5?

The Correct Answer Is:

Multiplying 7 by 5 means adding 7 five times (7+7+7+7+7) which equals 35. Option A is 7+5, and options C and D are incorrect calculations.

Real World Connection

In the Real World

When you buy groceries, if each packet of chips costs ₹15 and you buy 5 packets, you use multiplication by five to calculate the total bill quickly. Similarly, if you're saving ₹5 every day, you can multiply by the number of days to see how much you've saved.

Key Vocabulary

Key Terms

MULTIPLY: To find the product of two or more numbers | PRODUCT: The result of multiplying two or more numbers | TIMES: Used to show multiplication, meaning 'multiplied by' | REPEATED ADDITION: Adding the same number multiple times, which is what multiplication is.

What's Next

What to Learn Next

Now that you understand multiplying by five, you can move on to 'Multiplying by Ten' or 'Multiplying by Two'. These concepts build on your understanding of repeated addition and help you learn your multiplication tables faster.