Question:
If the number of five digit numbers with distinct digits and 2 at the 10th place is 336 k, then k is equal to :
If the number of five digit numbers with distinct digits and 2 at the 10th place is 336 k, then k is equal to :
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Fix 2 at the tens place, choose the leading digit (non-zero, not 2) first, then fill the other three places.
Updated On: Nov 5, 2026
- \(6\)
- \(8\)
- \(4\)
- \(7\)
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The Correct Option is B
Solution and Explanation
The tens place is fixed as 2. The ten-thousands place cannot be 0 or 2, so it can be filled in 8 ways.
The remaining three places (units, hundreds, thousands) must be filled with distinct digits from the 8 digits that are still unused (10 digits minus the digit 2 and the leading digit): \(8\times7\times6=336\) ways.
Total numbers \(=8\times336\).
Comparing with \(336k\): \(k=8\).
Answer: (2) 8
The remaining three places (units, hundreds, thousands) must be filled with distinct digits from the 8 digits that are still unused (10 digits minus the digit 2 and the leading digit): \(8\times7\times6=336\) ways.
Total numbers \(=8\times336\).
Comparing with \(336k\): \(k=8\).
Answer: (2) 8
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