Question 41 : Difference Between the Greatest 7-Digit Number and the Smallest 4-Digit Number

 

🧮 Difference Between the Greatest 7-Digit Number and the Smallest 4-Digit Number

Let’s solve a simple but interesting math question that often appears in school exams and entrance tests like JNVST.

Question 41

What is the difference between the greatest 7-digit number and the smallest 4-digit number?

Options:
(a) 9990999
(b) 9993999
(c) 9996999
(d) 9998999

Step 1: Identify the Numbers

  • The greatest 7-digit number is the largest number you can make using seven digits.
    👉 9,999,999

  • The smallest 4-digit number is the smallest number with four digits.
    👉 1,000

Step 2: Find the Difference

Now, subtract the smaller number from the larger one:

9,999,999−1,000=9,998,9999,999,999 - 1,000 = 9,998,999

Step 3: Choose the Correct Option

Let’s compare our answer with the options:

(a) 9990999 ❌
(b) 9993999 ❌
(c) 9996999 ❌
✅ (d) 9998999

So, the correct answer is option (d).

Step 4: Quick Tip

Here’s an easy way to remember:

  • The greatest n-digit number always has all 9s.
    Example: 7-digit → 9,999,999

  • The smallest n-digit number always starts with 1 followed by zeros.
    Example: 4-digit → 1,000

Whenever you see such a question, just write the two numbers clearly and subtract — it’s that simple!

Final Answer

✅ The difference between the greatest 7-digit number and the smallest 4-digit number is 9,998,999.

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