What is Ten Less Than?

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Grade Level:

Pre-School – Class 2

All domains without exception

Definition

What is it?

"Ten Less Than" means to subtract 10 from a given number. It helps us find a number that is smaller by exactly 10 units. This concept is a basic form of subtraction.

Simple Example

Quick Example

Imagine your favourite cricket team scored 150 runs in a match. If they had scored 'ten less than' that, how many runs would it be? It would be 150 - 10 = 140 runs.

Worked Example

Step-by-Step

Let's find what is 'ten less than 75'.

Step 1: Understand the phrase. 'Ten less than' means we need to subtract 10.
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Step 2: Identify the starting number. Here, the starting number is 75.
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Step 3: Set up the subtraction problem. We need to calculate 75 - 10.
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Step 4: Perform the subtraction. Subtract 0 from 5 in the ones place (5 - 0 = 5). Subtract 1 from 7 in the tens place (7 - 1 = 6).
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Step 5: Combine the results. The number is 65.

So, ten less than 75 is 65.

Why It Matters

Understanding 'ten less than' is crucial for quick mental math and building a strong foundation in subtraction. It's used by shopkeepers to calculate change, by engineers to adjust measurements, and even by scientists when comparing data sets.

Common Mistakes

MISTAKE: Adding 10 instead of subtracting. For example, calculating 'ten less than 30' as 30 + 10 = 40. | CORRECTION: Remember 'less than' always means subtraction. So, 30 - 10 = 20.

MISTAKE: Confusing 'ten less than' with 'less by ten'. While similar, sometimes students might write the numbers in the wrong order, like 10 - 70 instead of 70 - 10. | CORRECTION: The number after 'than' is always the starting number from which you subtract. So, 'ten less than 70' means 70 - 10.

MISTAKE: Making errors in subtraction, especially with borrowing. For example, calculating 'ten less than 23' as 10 - 23 or getting 12 instead of 13. | CORRECTION: Always double-check your subtraction. 23 - 10 = 13.

Practice Questions

Try It Yourself

QUESTION: What is ten less than 50? | ANSWER: 40

QUESTION: Your mom bought 65 ladoos for Diwali. If you eat ten less than that, how many ladoos would be left? | ANSWER: 55 ladoos

QUESTION: A bus had 82 passengers. At the next stop, ten passengers got off, and then 5 new passengers got on. How many passengers are on the bus now? | ANSWER: 77 passengers

MCQ

Quick Quiz

Which of these expressions represents 'ten less than 95'?

95 + 10

10 - 95

95 - 10

10 + 95

The Correct Answer Is:

The phrase 'ten less than' always means to subtract 10 from the given number. So, 'ten less than 95' is correctly written as 95 - 10. Options A and D involve addition, and Option B reverses the order of subtraction.

Real World Connection

In the Real World

When you check your mobile data balance, if it says you used 100 MB today, and yesterday you used 'ten less than' that, you can quickly figure out yesterday's usage. Similarly, a shopkeeper calculates the price of 1 kg of apples if the price is Rs 10 less than 2 kg.

Key Vocabulary

Key Terms

SUBTRACT: To take one quantity away from another | LESS THAN: A phrase indicating subtraction | DIFFERENCE: The result of subtracting one number from another | NUMBER: A count or measurement

What's Next

What to Learn Next

Great job mastering 'ten less than'! Next, you can explore 'ten more than' to understand how to add 10 to a number. These basic skills are building blocks for understanding larger additions and subtractions.