AP EAMCET · Maths · Permutation Combination
If \(8 \cdot{ }^7 P_r=7 \cdot{ }^8 P_{r-1}\), what is the value of \(r\) ?
- A 3 and 4
- B 2 and 5
- C 4 and 5
- D No solution (No such r exists)
Answer & Solution
Correct Answer
(D) No solution (No such r exists)
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\(8 \cdot{ }^7 P_r=7 \cdot{ }^8 P_{r-1}\)…
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