Question

Find the missing number :

• A. 5
• B. 40
• C. 41
• D. 81

Answer 1

The correct option is D 81

The numbers in each boxes are perfect squares.

As $1=1^2,4=2^2,9=3^2,16=4^2,25=5^2,36=6^2,49=7^2,64=8^2$

Hence the missing term $=9^2=81$.

$\therefore 81$ replaces question mark.