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What is 1000 - 1?
Grade Level:
Class 3
Maths, Computing, AI
Definition
What is it?
1000 - 1 means taking away one unit from the number 1000. It's a basic subtraction problem that helps us understand how numbers are ordered and how to count backwards.
Simple Example
Quick Example
Imagine you have 1000 rupees in your piggy bank. If you spend 1 rupee to buy a small toffee, how much money is left? You would have 999 rupees remaining. So, 1000 - 1 = 999.
Worked Example
Step-by-Step
Let's find the answer to 1000 - 1:
1. We start with the number 1000.
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2. We need to subtract 1 from it.
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3. Think of it as counting backwards one step from 1000.
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4. If you count backwards from 1000, the number just before it is 999.
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5. Therefore, 1000 - 1 = 999.
Answer: 999
Why It Matters
Understanding simple subtractions like 1000 - 1 is crucial for building strong math skills, which are vital in computing and even AI. In fields like data science or coding, you often need to calculate differences or manage quantities, where this basic understanding forms the base. Even game developers use such calculations to track scores or resources!
Common Mistakes
MISTAKE: Writing 1000 - 1 = 990 or 998 | CORRECTION: Remember that subtracting 1 means finding the number *immediately* before the original number. The number before 1000 is 999.
MISTAKE: Confusing subtraction with addition, and thinking 1000 - 1 is 1001 | CORRECTION: Subtraction means taking away, making the number smaller. Addition means adding, making the number bigger.
MISTAKE: Getting confused with place values when subtracting larger numbers | CORRECTION: For subtracting 1, simply identify the number that comes directly before the given number. No complex borrowing is needed here.
Practice Questions
Try It Yourself
QUESTION: What is 500 - 1? | ANSWER: 499
QUESTION: If a bus has 750 seats and 1 seat is empty, how many seats are filled? | ANSWER: 749
QUESTION: A building has 100 floors. If you are on the ground floor (floor 0) and want to go to the floor just below the 5th floor, which floor do you go to? (Hint: The 5th floor is counted as 5). | ANSWER: 4th floor
MCQ
Quick Quiz
What is the result of 1000 minus 1?
1001
999
990
100
The Correct Answer Is:
B
Subtracting 1 from 1000 means finding the number that comes just before 1000, which is 999. Options A, C, and D are incorrect as they either add 1, subtract more, or are completely different numbers.
Real World Connection
In the Real World
When you use a digital clock and the time goes from 10:00 to 09:59, that's like a 'minus 1' in minutes! Or, if a cricket team needs 1000 runs to win a series and they score 1 run, they now need 999 more runs. Even when you check your mobile data balance and it reduces by 1 MB, it's this basic concept in action.
Key Vocabulary
Key Terms
SUBTRACTION: Taking one number away from another | DIFFERENCE: The result of subtracting one number from another | PREDECESSOR: The number that comes immediately before another number | UNIT: A single item or quantity
What's Next
What to Learn Next
Great job understanding 1000 - 1! Now, you're ready to learn about subtracting larger numbers and mental math tricks. This will help you solve even bigger problems faster and more efficiently!
