in an examination hall there are four rows of chairs each row has 8 chairs one behind the other. Th

akshay

in an examination hall there are four rows of chairs each row has 8 chairs one behind the other. There are two classes sitting for the examination with 16 students in each class. It is desired that in each row, all student belong to the same class and that no two adjecent rows are alloted to the same class. In how many ways can these 30 students be sitted

HIMANSHU JAIN

look for the first row:

we pick 8 students from 1st class : 16C8

for next row, we pick 8 students from other class : 16C8

now for next two rows we have 8 students left for each row. so ,there's only one way to select them.

as we can start the row with either of the class's students so we multiply it with 2.

and students can arrange themselves in each row so, we have 4 times 8!.

so, ans : 2*16C8*16C8*8!*8!*8!*8!.

I hope u umderstood.

if any query u can ask me,..

Ask & Discuss Questions with Community & Experts