The correct option is D 20 cm
As the same wire is bent to form the square, the perimeters of the two figures will be equal.
Given,
Breadth of the rectangle = 10
We know that the perimeter of a rectangle = 2 (length + breadth)
= 2 x ( length + 10)
Given, side of the square = 15 cm
We know the perimeter of a square
= 4 x side
So, perimeter of the square = 4 x 15
= 60 cm
We have, perimeter of rectangle
= perimeter of square
So, 2 (length + 10) = 60
⇒ length + 10 = 30
⇒ length = 20 cm
Therefore, length of the given rectangle is 20 cm.