Inaugurated by IN-SPACe
ISRO Registered Space Tutor
S1-SA1-1024
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. When you subtract, you find out how much is left after removing some items.
Simple Example
Quick Example
Imagine you have 3 ladoos in a box. If you eat 1 ladoo, how many are left? You started with 3, took away 1, so 2 ladoos are remaining.
Worked Example
Step-by-Step
Let's find out what 3 - 1 is.
Step 1: Start with the first number, which is 3.
---
Step 2: Think of 3 objects. For example, imagine 3 cricket balls.
---
Step 3: The minus sign (-) means we need to take away or remove.
---
Step 4: The second number is 1. So, we need to take away 1 cricket ball from the 3 balls.
---
Step 5: If you had 3 balls and removed 1 ball, count how many are left.
---
Step 6: You will see that 2 cricket balls are left.
---
Answer: So, 3 - 1 = 2.
Why It Matters
Understanding simple subtraction like 3 - 1 is the foundation for all of maths, computing, and even AI. From calculating your daily expenses to coding a simple game or designing smart systems, subtraction helps us manage resources and make decisions. Engineers, data scientists, and even game developers use these basic ideas every day.
Common Mistakes
MISTAKE: Thinking 3 - 1 is the same as 1 - 3. | CORRECTION: Subtraction order matters! 3 - 1 means taking 1 from 3, while 1 - 3 means taking 3 from 1 (which gives a negative number). They are not the same.
MISTAKE: Counting up instead of counting down. For example, starting at 3 and counting 1, 2, 3. | CORRECTION: When you subtract 1 from 3, you count one step *back* from 3 on a number line, which lands you on 2.
MISTAKE: Forgetting what the minus sign means. | CORRECTION: The minus sign (-) always means 'take away', 'remove', or 'decrease by'.
Practice Questions
Try It Yourself
QUESTION: You have 3 pens. Your friend borrows 1 pen. How many pens do you have left? | ANSWER: 2 pens
QUESTION: A bus has 3 seats empty. One person gets on the bus and sits down. How many empty seats are left? | ANSWER: 2 empty seats
QUESTION: There were 3 children playing in the park. One child went home for lunch, and then another child joined them. How many children are playing now? (Hint: This needs two steps!) | ANSWER: 3 - 1 = 2. Then, 2 + 1 = 3. So, 3 children.
MCQ
Quick Quiz
Which of these correctly shows the result of 3 - 1?
The number 0
The number 1
The number 2
The number 3
The Correct Answer Is:
C
When you take away 1 from 3, you are left with 2. Options A, B, and D are incorrect because they do not represent the result of removing 1 from 3.
Real World Connection
In the Real World
Imagine you're checking your mobile data. If you started with 3 GB of data and used 1 GB watching videos, your phone's data usage tracker would show 2 GB remaining. This is simple subtraction used every day!
Key Vocabulary
Key Terms
SUBTRACTION: The process of taking one number or quantity away from another to find the difference. | MINUS SIGN (-): The symbol used to show subtraction. | DIFFERENCE: The result you get after subtracting one number from another. | REMAINDER: What is left after a part is taken away.
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, subtracting zero, and even how subtraction relates to addition. Keep practicing, it makes maths much easier!
