At a wedding, the close family members of the couple are to be sat on

Question

At a wedding, the close family members of the couple are to be sat on 2 rows close to the front. Both tables have 6 seats arranged from left to right. There are 15 family members who could be offered a seat on the rows. Which of the following is equal to the number of possible arrangements of the family members on the first two rows?

(A) \(\frac{15!}{2!}\)

(B) \(\frac{15!}{3!}\)

(C) \(\frac{15!}{6!}\)*\(\frac{9!}{6!}\)

(D)\((\frac{15!}{9!})^2\)

(E) 2(\(\frac{15!}{12!}\))

(A)  \frac{15!}{2!}

(B)  \frac{15!}{3!}

(C)  \frac{15!}{6!} * \frac{9!}{6!}

(D) (\frac{15!}{9!})^2

(E) 2( \frac{15!}{12!} )

Peddi · Answer

The question asks about arrangements, in the first row out of 15 people 6 should be arranged=15p6, now for the second row 9 people are left 6 out of 9 people should be arranged no of ways= 9p6 , now total no of ways= 15p6 *9p6 = 15!/3!

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GMATWhizTeam · Answer

Solution:

There are 12 seats available in the first 2 rows.
 https://www.dropbox.com/s/9p9dk8rbhyhddlq/41.jpg?dl=1 
 o For the first seat there 15 choices
 o For the second seat there are 15 – 1 = 15 choices, so on… 
o The total number of arrangements=  15*14*13*12*11*10*9*8*7*6*5*4 = \frac{15!}{3!} . 
Hence, the correct answer is  Option B

Dooperman · Answer

15 People and 12 Seats.

Select 12 out of 15 people to be seated = 15C12

Arrange these 12 people on 12 seats = 12!

Total arrangements = 15C12 * 12! = (15! / 3!)

Dooperman · Answer

15 People and 12 Seats.

Select 12 out of 15 people to be seated = 15C12

Arrange these 12 people on 12 seats = 12!

Total arrangements = 15C12 * 12! = (15! / 3!)

Rishm · Answer

So 12 people can be selected out of 15 that makes 15!/3!*12!, if you solve this you will get 15*14*13/3!, now 12! is the way they are arranged internally, hence 15!/3! back to sqaure one.

At a wedding, the close family members of the couple are to be sat on

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At a wedding, the close family members of the couple are to be sat on

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