Question

Observe the given rectangle

what is the minimum number of balls we need to remove to make it a square?

• A. 3
• B. 6
• C. 9
• D. 12

Answer 1

The correct option is A

3

We can observe from the figure that the rectangle has

$4\times 3=12$ dots in it.

For a square, we must have an equal number of rows and column.

To make it a square we must remove one row from it, i.e., we need to remove 3 dots.

Now, rows and columns both becomes 3, and number of balls becomes $3\times 3=3^2=9$