Question

A family of 13 members went for a picnic at a park. There they saw a long straight bench that could accommodate all of them so they decided to sit on it. Now, the two youngest members of the family had an argument the previous day so they refused to sit together. What is the probability that out of all seating arrangements that are possible, one arrangement is picked such that the two youngest members don't sit together?​

Answer 1

Answer:

12/78or 2/13

Step-by-step explanation:

make all the arrangements possible , let the two youngest members be 1 and 2

then 1 will make pair with 3,4,5,6,7,8,9,10,11,12,13 = 12 pairs,1 won't make with 2 according to question

2 will make = 3,4,5,6,7,8,9,10,11,12,13 = 11 pairs

then 3 will make with 4,5,6,7,8,9,10,11,12,13 = 10 pairs , not with 1 and 2 as they made pair before

then 4 will make 5,6,7,8 and so on

And then you make pairs with all numbers

therefore total pairs formed with 1 = 12 , 2= 11 , 3=10 and so on till 78 pairs

total persons sitting together 12

12/78 = 2/13

Answer 2

Answer:

Step-by-step explanation:

11/13

total member 13

2 won't sit with each other