Math, asked by aksharn47, 22 hours ago


If np6=20×np4, then find the value of n​

Answers

Answered by RJPrathishaa
0

Answer:

n=7

Step-by-step explanation:

Correct option is

A

7

n

P

4

=20×

n

P

2

(n−4)!

n!

=20

(n−2)!

n!

⇒(n−2)(n−3)=20

⇒n

2

−5n−114=0

⇒(n−7)(n+2)=0

n=7,−2

As n>0

n=7

solution

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SIMILAR QUESTIONS

star-struck

Find the value of n such that

n

P

5

=42(

n

P

3

):n>4.

Hard

View solution

>

If 5.

n

P

3

=4.

n+1

P

3

,

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