Question

NP4 = 42 x nP2 maka nP3 adalah

Answer 1

NP4 = 42 × nP3
n! / (n-4)! = 42 . n! / (n-3)!
1/42 = (n-4)! / (n-3)(n-4)!
1/42 = 1/(n-3)
n-3 = 42
n = 42+3
n = 45

nP3
= 45P3
= 45! / (45-3)!
= 45! / 42!
= 45 × 44 × 43 × 42! / 42!
= 45 × 44 × 43
= 85140

Answer 2

NP4 = 42 . nP2
n! / (n-4)! = 42. n! / (n-2)!
(n-2)! / (n-4)! = 42. n!/n!
(n-2)(n-3) = 42
(n-2)(n-3) = 7(6)
n = 9
.
nP3 = 9 P3 = 9 !/ (6!)= 9x8x7 = 504