Question:
How many numbers between 100 and 999 can be formed with the digits 1, 4, 7, 8, and 9 if the digits are not repeated?
How many numbers between 100 and 999 can be formed with the digits 1, 4, 7, 8, and 9 if the digits are not repeated?
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3 slots: 5 choices for the first, 4 for the second, 3 for the third. Multiply them!
Updated On: May 13, 2026
- 20
- 60
- 12
- 120
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Verified By Collegedunia
The Correct Option is B
Solution and Explanation
Step 1: Concept
This is a permutation problem where we select 3 digits out of 5 available digits without replacement.
Step 2: Meaning
Numbers between 100 and 999 are 3-digit numbers. We have 5 digits available: {1, 4, 7, 8, 9}.
Step 3: Analysis
Total numbers = $^5P_3 = 5 \times 4 \times 3$.
Step 4: Conclusion
$5 \times 4 \times 3 = 60$. There are 60 such numbers. Final Answer: (B)
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