Permutations And Combinations

Question
CBSEENMA11014217

If straight P presuperscript straight n subscript straight r space equals space straight P presuperscript straight n subscript straight r plus 1 end subscript space and space straight C presuperscript straight n subscript straight r space equals space straight C presuperscript straight n subscript straight r minus 1 end subscript comma find n and r.

Solution

Solution not provided.
Ans. n = 3, r = 2

Some More Questions From Permutations and Combinations Chapter

Determine K, so that K + 2, 4K – 6 and 3K – 2 are three consecutive terms of an A.P.