Question

Which number will be placed at the sign of interrogation?

• A. 21
• B. 25
• C. 50
• D. 60

Answer 1

Answer: (B)

25

The numbers on the top of the tree are perfect squares.
In image 1,
$\sqrt{4}\times \sqrt{9}=6$
$2\times 3=6$
Similarly in Image 2, the same rule is followed
Therefore, in Image 3
$\sqrt{16}\times \sqrt{x}=20$
$4\times \sqrt{x}=20$
$\sqrt{x}=5$
$x=25$
Answer is Option B