Question:medium
If \( ^{56}P_{r+6} : \, ^{54}P_{r+3} = 30800 : 1 \), then \( r \) is equal to
If \( ^{56}P_{r+6} : \, ^{54}P_{r+3} = 30800 : 1 \), then \( r \) is equal to
Show Hint
In permutation ratios, always expand factorials to cancel terms instead of calculating full factorial values.
Updated On: May 1, 2026
- \( 69 \)
- \( 41 \)
- \( 51 \)
- \( 61 \)
- \( 49 \)
Show Solution
The Correct Option is B
Solution and Explanation
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