Question

in how many ways can the members be arranged around a circle so that there is exactly one female between the two sister present in a group of 20 kittes members​

Answer 1

Step-by-step explanation:

Let us fix one person called P and the two sisters called X and Y . So let's form a group of two sisters and one person X P Y . Hence,the person is fixed in the middle and two ways to arrange two sisters X P Y and Y P X .

Now, assuming total people = 17 ( 16 people and 1 group of X , Y , and P ) . So arrangement = 17 !

Each person out of 18 can be fixed between the two = 18 .

Final Answer = 2 * 17 ! * 18

= 2 * 18 !