Question

During a mass drill exercise, 6,250 students of different schools are arranged in rows such that the number of students in each row is equal to the number of rows. In doing so, the instructor finds out that 9 children are left out. Find the number of children in each row.

• A. 77
• B. 79
• C. 70
• D. 97

Answer 1

The correct option is B 79

Total number of students = 6,250
Number of students forming a square
= 6,250 - 9
= 6,241

Thus, 6,241 students form a big square which has number of rows equal to the number of students in each row.

Let the number of students in each row be $x$, then the number of rows $=x$
Therefore, $x\times x=6241$
$x^2=6241$
$\sqrt{x}=\sqrt{6241}=79$

Hence, there are 79 students in each row of the square formed.