18-02-2017
Mathematics

contestada

How to solve for n using my knowledge of permutations

How to solve for n using my knowledge of permutations class=

Respuesta :

sheheryar91 sheheryar91

18-02-2017

NP5=18*N-2P4
N!/(N-5)!=18*(N-2)!/(N-6)!

(N(N-1)(N-2)!)/(N-5)*(N-6)!=18*(N-2)!/(N-6)!
N(N-1)/N-5=18
N^2-N=18N-90
N^2-19N-90=0
N=9,N=-10
-10 is not possible so N=9

Answer Link

Otras preguntas

CAN SOMEONE PLS HELP ME A group pre-orders 9 tickets for a sightseeing tour, even though they don't have the money to pay for them yet. Each ticket costs $32, s

A paper cup is dropped and its landing position is recorded. The cup can land on the side, on the open end, or on the closed end. The results of 20 trials are s

What is the current total fertility rate (tfr) for the world as a whole?

Choose the missing number to make equivalent fractions. 1/4=?/16 A. 2 B. 4 C. 6 D. 8

What’s the square root of PI

helpppp... I suck at algebra. the question is down below 7x(-3)x(-2)^2

F(x) = 4x2 + 5x – 2 g(x) = 5x – 2x2 – 3x + 4 Which function represents the sum of the functions, h(x) = f(x) + g(x)?

What is the main cause of mass wasting? A.Gravity B.Biology C.Glaciers D.Chemicals

What do you do if a girl takes off her clothes in front of you?

Evaluate the following please.