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What is 3 - 1?
Grade Level:
Class 1
Maths, Computing, AI
Definition
What is it?
3 - 1 means taking away 1 from the number 3. It is a basic subtraction problem. Subtraction helps us find how many are left when some items are removed from a group.
Simple Example
Quick Example
Imagine you have 3 ladoos. If you eat 1 ladoo, how many ladoos are left for you? You had 3, you took away 1. So, 3 - 1 = 2 ladoos.
Worked Example
Step-by-Step
Let's find the answer to 3 - 1 using a number line.
Step 1: Start at the number 3 on the number line.
---Step 2: The minus sign (-) tells us to move backwards or to the left.
---Step 3: The number 1 tells us to move backwards by 1 step.
---Step 4: Move 1 step to the left from 3.
---Step 5: You land on the number 2.
So, 3 - 1 = 2.
Why It Matters
Understanding simple subtraction like 3 - 1 is the building block for all advanced maths, computing, and even AI. Computer programmers use subtraction for calculations in games and apps. Data scientists use it to compare numbers and find differences in large datasets. It's crucial for careers in finance, engineering, and technology.
Common Mistakes
MISTAKE: Adding the numbers instead of subtracting, getting 3 + 1 = 4. | CORRECTION: Always check the operation sign. The '-' sign means 'take away'.
MISTAKE: Counting forward from 3 instead of backward, getting 3 + 1 = 4. | CORRECTION: For subtraction, you always move backwards or count down from the first number.
MISTAKE: Confusing 3 - 1 with 1 - 3. | CORRECTION: The order matters in subtraction. 3 - 1 is not the same as 1 - 3. Always start with the first number and take away the second.
Practice Questions
Try It Yourself
QUESTION: You have 3 cricket balls. If you lose 1 ball, how many are left? | ANSWER: 2
QUESTION: A bus has 3 passengers. If 1 passenger gets off at the next stop, how many passengers remain on the bus? | ANSWER: 2
QUESTION: Your mobile phone has 3GB of data. You use 1GB for watching videos. How much data is left? If you then use 1 more GB, how much is left in total? | ANSWER: 2GB left after first use. 1GB left in total.
MCQ
Quick Quiz
What is the result of 3 - 1?
1
2
3
4
The Correct Answer Is:
B
3 - 1 means taking away 1 from 3. If you have 3 items and remove 1, you are left with 2 items. So, 2 is the correct answer.
Real World Connection
In the Real World
Imagine you are helping your parents manage household expenses. If an item costs 3 rupees and you pay with a 4-rupee coin, you need to calculate 4 - 3 = 1 rupee change. This simple subtraction is used every day at local kirana stores, vegetable markets, and even when checking your bank balance after a UPI payment.
Key Vocabulary
Key Terms
SUBTRACTION: The process of taking one number or quantity away from another | MINUS SIGN (-): The symbol used to show subtraction | DIFFERENCE: The result of subtracting one number from another | NUMBER LINE: A straight line with numbers placed at equal intervals
What's Next
What to Learn Next
Great job understanding 3 - 1! Now that you know basic subtraction, you can learn about subtracting larger numbers, subtraction with borrowing, and even how subtraction is used in algebra. Keep practicing!
