What is a Subtraction Sentence?

S0-SA1-0137

Grade Level:

Class 1

Maths, Logic, NLP

Definition

What is it?

A subtraction sentence is a way to write down a subtraction problem using numbers, a minus sign (-), and an equals sign (=). It shows how many are left when you take away one number from another. It always follows the pattern: 'Big Number - Small Number = Difference'.

Simple Example

Quick Example

Imagine you have 5 delicious ladoos. If your friend eats 2 of them, how many ladoos are left? The subtraction sentence for this would be: 5 - 2 = 3.

Worked Example

Step-by-Step

Let's say your dad gave you 100 rupees for pocket money. You spent 30 rupees on a new pen. How much money do you have left?

1. Identify the total amount: Your dad gave you 100 rupees. This is the 'big number'.
---2. Identify the amount taken away: You spent 30 rupees. This is the 'small number'.
---3. Write the subtraction sign: Place a minus sign (-) between the numbers.
---4. Write the equals sign: Place an equals sign (=) after the small number.
---5. Calculate the difference: 100 - 30 = 70.
---6. Complete the sentence: 100 - 30 = 70.

So, you have 70 rupees left.

Why It Matters

Understanding subtraction sentences is key to solving everyday problems, from managing your daily expenses to understanding cricket scores. It's a basic building block for advanced Maths and even helps in computer programming (Logic) when you need to calculate differences. People in finance, engineering, and data analysis use these concepts daily.

Common Mistakes

MISTAKE: Writing the smaller number first (e.g., 5 - 10 = ?). | CORRECTION: Always start with the larger number (the total) from which you are taking something away. It should be Total - Taken Away = Left.

MISTAKE: Confusing the minus sign (-) with the plus sign (+). | CORRECTION: Remember, the minus sign means 'take away' or 'find the difference', while the plus sign means 'add together' or 'find the total sum'.

MISTAKE: Not writing the equals sign (=) or the final answer. | CORRECTION: A complete subtraction sentence always shows the 'big number', the minus sign, the 'small number', the equals sign, AND the 'difference' (the answer).

Practice Questions

Try It Yourself

QUESTION: Your mom baked 12 cookies. You ate 3. Write the subtraction sentence. | ANSWER: 12 - 3 = 9

QUESTION: A bus started with 35 passengers. At the first stop, 10 passengers got off. What is the subtraction sentence for the number of passengers left? | ANSWER: 35 - 10 = 25

QUESTION: Your favourite mobile game has 50 levels. You have completed 25 levels. If you play 5 more levels today, how many levels are still left to complete? Write two subtraction sentences to show this. | ANSWER: First: 50 - 25 = 25 (levels left initially). Second: 25 - 5 = 20 (levels left after today)

MCQ

Quick Quiz

Which of these is a correct subtraction sentence?

7 + 3 = 10

15 - 5

8 - 2 = 6

4 = 9 - 5

The Correct Answer Is:

Option C (8 - 2 = 6) is a complete and correct subtraction sentence as it shows the total, the minus sign, the number taken away, the equals sign, and the difference. Option A is addition, Option B is incomplete, and Option D has the equals sign in the wrong place for a standard subtraction sentence.

Real World Connection

In the Real World

When you check your mobile data usage, the app often shows your total data and how much you've used, then calculates 'data remaining' using a subtraction sentence. Similarly, while budgeting for your school trip, you subtract expenses from your total savings to see how much is left.

Key Vocabulary

Key Terms

SUBTRACTION: The process of taking one number or quantity away from another | MINUS SIGN (-): The symbol used to show subtraction | EQUALS SIGN (=): The symbol used to show that two things are the same or equal | DIFFERENCE: The answer you get when you subtract one number from another | SENTENCE: A complete way of writing a mathematical idea with numbers and symbols.

What's Next

What to Learn Next

Great job understanding subtraction sentences! Next, you can explore 'Addition Sentences' to see how they are similar yet different. After that, you'll be ready for 'Word Problems with Subtraction' where you'll apply these sentences to solve real-life stories.