Question
How many numbers lying between 999 and 10000 can be formed with the help of the digits 0,2,3,6,7,8, when the digits are not repeated?
BITSAT
Mathematics
Permutation Combination
2021
BITSAT 2021
BITSAT Mathematics Question (2021) — Solution
Options
- A. 100
- B. 200
- C. 300
- D. 400
Answer
C. 300
Step-by-step solution
The numbers between 999 and 10000 are all 4-digit numbers. The number of 4 - digit numbers formed by digits 0,2,3,6,7,8 is ^ 6 P _ 4 =360. But here those numbers are also involved which begin from 0 . So, we take those numbers as three-digit numbers. Taking initial digit 0 , the number of ways to fill remaining 3 places from five digits 2,3,6,7,8 are ^ 5 P _ 3 =60 So, the required numbers =360-60=300.
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