Question

Two variants of a test paper are distributed among $12$ students. Number of ways of seating of the students in two rows so that the students sitting side by side do not have identical papers and those sitting in the same column have the same paper is

• A. $\frac{12!}{6!6!}$
• B. $\frac{\left(12\right)!}{2^5.6!}$
• C. $(6!{)}^2.2$
• D. $12!\times 2$

Answer 1

The correct option is D $12!\times 2$

Number of variants test $=2$

Total number of students $=12$

$\therefore$ They can be arranged in $12!$ ways

As the students are seated in two rows,

The probability of arranging the students so that near by students don't have identical papers

$=12!\times 2$

Hence, the answer is $12!\times 2.$