If 6Pr = 360 and If 6Cr = 15, find r ?
A. 5
B. 6
C. 4
D. 3
Answer: Option C
Solution(By Examveda Team)
nPr = nCr × r! 6Pr = 15 × r! 360 = 15 × r! r! = $$\frac{{360}}{{15}}$$ = 24 r! = 4 × 3 × 2 × 1 ⇒ r! = 4! Therefore, r = 4Related Questions on Permutation and Combination
A. 3! 4! 8! 4!
B. 3! 8!
C. 4! 4!
D. 8! 4! 4!
A. 7560,60,1680
B. 7890,120,650
C. 7650,200,4444
D. None of these
A. 8 × 9!
B. 8 × 8!
C. 7 × 9!
D. 9 × 8!
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